Caesar is an evolved chimpanzee, the leader of the Ape Army, the king of the Ape Colony and the patriarch of the Royal Ape Family. He is also the biological son of the late Alpha and the late Bright Eyes, the adoptive son of the late Will Rodman and the late Caroline Aranha, the adoptive grandson of the late Charles Rodman, the husband of Cornelia, the father of Blue Eyes and Milo and the ape counterpart of Malcolm. In Rise of the Planet of the Apes, Caesar is raised by Will and Caroline after the death of his mother, but he is banished to live in captivity at the San Bruno Primate Shelter after he violently attacks a neighbour. However, he later leads fellow apes in a rebellion against abusive handlers and the police then makes an attempt at world domination by unleashing Gen-Sys Laboratories' deadly virus strain, which isn't lethal to primates, only the human population. In Dawn of the Planet of the Apes, Caesar tries to maintain domination over his community of intelligent apes while also having to deal with the threat of war after a group of human survivors suddenly reemerge after it is believed that humanity had been pushed to extinction due to the Simian Flu Pandemic.
Caesar is marvelously unique by intellectual means. Due to his inheriting the drugs used on his mother, he is incredibly intelligent, dangerously cunning and viciously ruthless. He developed quick relationships with humans, unlike some of the other apes, and seemed to be almost mutually connected with them. He is unusually cynical and attacked one of his neighbors with spiteful intent when the latter threatened his adoptive human grandfather. Incredibly, he is capable of leading vast armies of delusional, deranged apes into battle, showing charisma, loyalty, cerebrality, social mastery and dedication to his kind. Also, he is shown to be quite vengeful as he would strike out the moment he or a close friend/relative of his is threatened and would sometimes try or kill his enemies. He is a brilliant tactician, shown in the Battle on the Golden Gate Bridge, and used strategic excellence in the skirmish and used all of the advantages he had at his disposal. Caesar has several human emotions that the other apes didn't share; fear, happiness, triumph, concern, sympathy, compassion and independence. He is bound by his loyalty to his human companions and his fellow apes. In the climax of the battle, Caesar shows a darker side; the one thing that all of his apes shared that day; revenge. He was distraught and angry at Buck's death and was about to take his revenge on Steven Jacobs for his friend's death. He then showed a cruel side to him when he coldly walked away and left Koba, twice as vengeful and cruel then Caesar, to deal with the man. At the end of the film, he shows his true connection to mother nature when he says to his former owner, and adoptive human father Will, indicating his dedication to his fellow comrades; "Caesar is home".
Dr. Will Rodman, under the employment of Gen-Sys Laboratories, has been working with apes using ALZ-112 - gene cells through neurogenesis - in the hopes of finding a cure for Alzheimer's disease. A female chimpanzee named Bright Eyes is given the ALZ-112 drug, which not only repairs brain cells, but increases her mental capabilities as well. Two months into her trial while being forcibly removed from her cage, Bright Eyes goes on a rampage throughout the facility before security is forced to kill her in front of the board members. Believing the outburst to have been caused by the drug, head of Gen-Sys Laboratories, Steven Jacobs, orders all remaining apes euthanized, destroying any chance of developing ALZ-112 any further. It is discovered, however, that Bright Eyes' aggression was not due to the drug, but to her maternal instinct to protect her newborn baby whom she had secretly given birth to a day or two earlier. Robert Franklin, the chimp handler, responsible for carrying out the euthanasia order, can't bring himself to kill the infant and instead gives it to Will who manages to smuggle the infant out of the facility and take it home with him.
At first, Will intends that the baby chimp was just a "temporary house guest", but his Alzheimer's-afflicted father, Charles Rodman's caretaker, Irena, wonders if having a pet might be good for him. This idea proves true when Charles instantly starts to get attached to the baby chimp. The baby chimp is given the name Caesar by Charles, who, upon holding the infant, quotes Shakespeare's Julius Caesar, "but as for Caesar, kneel down, kneel down, and wonder". Bearing the same white shooting star birthmark as his father, Alpha, Caesar is incredibly intelligent for an ape of his age, immediately learning how to nurse from a bottle on his own at only two days old. His quick learning and the flecks of green present in his irises, a side effect of ALZ-112 treatment, makes Will decide to keep Caesar and raise him as his own, monitoring the ape and continuing to work on the ALZ-112 drug in secret. Right away, Caesar displays signs of heightened intelligence, learning up to twenty-four words in sign language by eighteen months of age, completing puzzles and models designed for human children eight years and up, at age two, and able to play chess and complete a Lucas' Tower puzzle with a perfect score of fifteen moves at age three, continuing to show cognitive skills far exceeding that of a human counterpart. Will hypothesises that Caesar's heightened intelligence is a result of the ALZ-112 virus being passed down genetically from Bright Eyes to Caesar in utero and that in the absence of damaged brain cells that need replacing, the drug instead radically boosts healthy brain functions.
Caesar then stole cookies that belong to Dodge and gave them to Rocket who while tempted to eat all the cookies he ultimately shared with the others which earned him the respect from Rocket. The next day, Maurice asked Caesar why he gave the cookie to Rocket and Caesar using sign language said that apes must stand together to be strong. As this was happening the pair noticed a pair of apes playing in the water and acting foolishly, prompted Maurice to say "Apes stupid". This statement had gave Caesar an idea and he decided to escape from the primate shelter in order to find a way to make the other apes smarter. That night, he traveled back to Will's house. Caesar entered the house through Will and Caroline's bedroom window where after looking upon his sleeping adoptive parents he went into the kitchen where he stole some canisters of "ALZ-113" and after inhaling some of the gas he gained more intelligence with his eyes turning more green in the process. Realizing this is what he needed to enhance the intelligence of the other apes he returned to the facility where he punctured the canisters and released the gas throughout the cage area which further enhanced the intelligence and mental capabilities of himself and his fellow apes. The next day, when all the apes were being sent to the play area Caesar examined the apes and saw that they now possess green eyes, a sign that they have gained intelligence and are now Evolved Apes like him. Caesar then organized the apes and told them of his plan of leading them to freedom in the Muir Woods Park. Dodge, the sadistic caretaker noticed Caesar in the play area when he was not supposed to be with the other apes watching this act. A brief scuffle ensued with Dodge hitting Caesar with the electrical cattle prod multiple times but soon ended with Caesar catching the prod. Dodge, angered and struggling stated "Take your stinking paw off me, you damn dirty ape!". Caesar then showed his first capability of human speech by shouting "NO"! at Dodge, leaving him, Rodney and Buck shocked, after which Caesar knocked the surprised human out by hitting him with the prod. He then took the incapacitated Dodge to the cages where he freed the other apes though the remaining watchman Rodney entered the scene but seeing he was outnumbered he tried to escape however, he was grabbed and the apes proceeded to beat him until Caesar stopped them. Knowing that Rodney was a more kinder human than Dodge, Caesar instead calmly locked the scared Rodney in a cage. As he did so Dodge regained consciousness and got out his cage this didn't go unnoticed by the apes who began moving in on him. Dodge then tried to get the water hose, Caesar pulled it back, making Dodge grabbed his electric cattle prod saying he will skin every one of them before running at Caesar, who sprayed him with the hose while his electric cattle prod was in his hand, electrocuting and killing him. Horrified, at his deed Caesar grieves before looking upon an ape tag and deciding to move ahead with his plans and liberate all the other captive apes in the city. He frees Buck from his cage and the apes at the facility then escaped into the night by breaking the windows above the play area and climbing through them. Arriving at the outskirts of the city, Caesar divided the ape forces into two groups with one faction led by Buck to invade the Zoo while the other with himself, Rocket and Maurice which headed to the Gen-Sys Laboratories, as he knew some of the sheltered apes - such as Cornelia and Lucky who had been there for experimentation. Caesar's group released all the apes there (including Koba) while Buck's group broke into the San Francisco Zoo not only liberating countless apes but the bars from the ape cage's at the Zoo gave the evolved apes new weapons to combat the humans. Caesar successfully led an army of hundreds of apes through the streets of San Francisco putting the city to a massive panic. The apes battled through multiple police and animal control threats of the city and using a trolley they headed to Golden Gate Bridge, as their next stop to freedom.
Ten years after the worldwide pandemic of the deadly Simian Flu, human civilization is completely destroyed all over the world. Over 99% of the human population has died in the pandemic while apes with genetically enhanced intelligence have started to build a civilization of their own. Near the ruins of San Francisco, Caesar reigns supreme over the ever growing Ape Colony residing in Muir Woods. His people have learned sign language in order to communicate with one another, medical and combat training to care for and defend themselves as well as hunting as a way of life. He also forges the Ape Council consisting of his closest friends, Maurice, Rocket and Koba. Later in life, Caesar and his wife, Cornelia, have a son named Blue Eyes (due to his blue irises) who is inducted into the Ape Army and the Ape Council by his father in order for him to learn how to operate an empire that will one day be his own.
On a hunt for elk, Caesar successfully ensnares a stag. Before proceeding to kill the stag, Caesar notices, to his concern, large claw marks on a nearby tree and orders his son to wait. Blue Eyes, however, disobeys his father's order and attempts to kill the stag, but is attacked by a bear. Caesar, attempting to protect his wounded son and fight the bear, stands no chance and immediately calls for help. His call is eventually heard by Koba who kills the bear by spearing it in the back of the head, trapping Caesar underneath its corpse. However, Caesar emerges from underneath the corpse. He thanks Koba for the assistance and reprimands Blue Eyes for his recklessness before they return to the Ape Village. Returning to the village, Caesar is summoned to his home where he witnesses the birth of his youngest son, Milo. He summons over Blue Eyes to meet his new younger brother and together, the Royal Ape Family celebrates the new addition to their family and colony. Later that afternoon, Maurice congratulates Caesar on the birth, but the subject changes to humans who haven't been seen for the last ten winters. Maurice believes that the humans are all gone, but Caesar still questions the humans' eradication.
Awakened by the sound of a gunshot, Caesar quickly makes his way through the forest until he discovers a group of humans led by a man named Malcolm, much to his shock. Malcolm tries to reassure the apes that the humans mean no harm to them, but since one of the humans shot Ash, the son of Rocket, wounding him. Caesar angrily orders the humans to leave. The humans quickly depart, but Caesar orders Koba to follow them, leading the apes to discover a community of human survivors in the city who are genetically immune to the virus and living in a tower within the city. Back at the village, Caesar and the Council discuss what should be done about the humans. Koba insists on fighting the humans, but Caesar acknowledges that war could cost them their home. He assures the Council that he will have a decision by morning before retiring to his home. However, Koba approaches Caesar and tells him of his past, that he will obey his commands without hesitation, but the apes must show strength. Caesar agrees. Marching to the tower, Caesar announces to the terrified humans that while apes do not want war, they will fight to defend their home, warning the humans to never come back to the forest before the apes depart. However, Malcolm and his party return to the forest despite Caesar's warning. Malcolm travels into the apes' territory and is captured by the Gorilla Guardians, the protectors of the forest, and is taken to Caesar. Malcolm tells Caesar that if he just allows him to show him, he will understand why the humans are trespassing into his territory. Caesar accepts Malcolm's proposal. Malcolm then takes Caesar and several other apes to a hydroelectric dam where he explains that the humans need to repair the dam's generator, which could provide long-term power to the city and therefore they will be able to reach the outside world and hopefully find other survivors. Sympathetic to the humans, Caesar allows them to stay and repair the dam's generator, but they must work unarmed.Awakened by the sound of a gunshot, Caesar quickly makes his way through the forest until he discovers a group of humans led by a man named Malcolm, much to his shock. Malcolm tries to reassure the apes that the humans mean no harm to them, but since one of the humans shot Ash, the son of Rocket, wounding him. Caesar angrily orders the humans to leave. The humans quickly depart, but Caesar orders Koba to follow them, leading the apes to discover a community of human survivors in the city who are genetically immune to the virus and living in a tower within the city. Back at the village, Caesar and the Council discuss what should be done about the humans. Koba insists on fighting the humans, but Caesar acknowledges that war could cost them their home. He assures the Council that he will have a decision by morning before retiring to his home. However, Koba approaches Caesar and tells him of his past, that he will obey his commands without hesitation, but the apes must show strength. Caesar agrees. Marching to the tower, Caesar announces to the terrified humans that while apes do not want war, they will fight to defend their home, warning the humans to never come back to the forest before the apes depart. However, Malcolm and his party return to the forest despite Caesar's warning. Malcolm travels into the apes' territory and is captured by the Gorilla Guardians, the protectors of the forest, and is taken to Caesar. Malcolm tells Caesar that if he just allows him to show him, he will understand why the humans are trespassing into his territory. Caesar accepts Malcolm's proposal. Malcolm then takes Caesar and several other apes to a hydroelectric dam where he explains that the humans need to repair the dam's generator, which could provide long-term power to the city and therefore they will be able to reach the outside world and hopefully find other survivors. Sympathetic to the humans, Caesar allows them to stay and repair the dam's generator, but they must work unarmed.
Returning to the village, Caesar is at ease with the humans' presence in the forest unlike Koba who is angry that Caesar is choosing to help the humans rather than attack them. However, Caesar informs Koba that the apes and the humans have only one chance for peace, but Koba's hatred for humans only grows stronger, driving a wedge between the honorary brothers. As the humans proceed to repair the dam's generator, they bond with the apes. Mutual distrust of both sides gradually subsides. During their progression, the humans are suddenly trapped underground due to an explosion, but Caesar and his fellow apes rescue them after they had been informed of the humans' situation by Ellie, a nurse and Malcolm's wife, and Alexander, Malcolm's son. While the humans are being treated for their injuries, Malcolm thanks Caesar for the assistance, but before anything else can be said, Milo scurries out of Blue Eyes' arms to investigate the humans. However, the genocide between the apes and the humans returns when Carver, who holds a deep hatred for the apes, threatens Blue Eyes with a concealed shotgun, enraging his father who almost kills Carver. Caesar, in his betrayed fury, threatens the humans with the shotgun, but instead, tosses it into the lake. Departing with both of his sons, Caesar furiously orders the humans to leave at once. Back at the village, Caesar discovers, to his grief, that his wife is seriously ill. Weeping over his sick wife, Caesar receives a visit from Malcolm and Ellie who had followed him back to the village, begging for him to reconsider as they did not know about the shotgun. Caesar, however, hasn't forgotten the recent incident and is not at all pleased by their presence in his home, ignoring their pleas. Ellie then notices Cornelia and offers to treat her with antibiotics, but Caesar doesn't trust them anymore. Despite his distrust and his son's protests, Caesar allows Ellie to treat Cornelia, allowing the humans only one day to finish their work with the apes' help.
Meanwhile, Koba returns to the village after infiltrating the city along with his followers, Stone and Grey, and discovering an armory in secret. After learning from Blue Eyes that Caesar is still assisting the humans at the dam despite that they have threatened both of his sons. Koba confronts Caesar, accusing him of loving humans more than apes and more than his own sons. In response, an enraged Caesar severely beats Koba, but refrains from killing him, adhering to his philosophy that "ape not kill ape". Koba asks for forgiveness and Caesar hesitantly forgives him. However, the brutal fight has permanently broken their relationship beyond repair. While Caesar continues to assist the humans, Koba begins to secretly plan to overthrow him. The dam is eventually repaired with the combined efforts of the apes and the humans, restoring power to the city. Caesar invites the humans back to the village to celebrate. During the celebration, however, Grey, under Koba's orders, sets fire to the apes' home, then, unseen to anyone else, Koba shoots Caesar in the shoulder with an assault rifle that he stole from the humans' armory, causing Caesar to fall from the settlement's main tree, much to the horror and grief of his people, especially Cornelia and Blue Eyes. In the panic of the loss of the alpha and the threat of the fire, Koba takes charge and, implicating Carver whom he secretly murdered in the shooting, urges his people to fight against the humans, promising to avenge the death of their beloved king.
Malcolm's group, who had successfully hidden from the outraged ape army, find Caesar barely alive who reveals to Malcolm that Koba shot him, not Carver. The group return and discover the city in flames due to the apes' earlier assault on the city. Despite heavy causalities, the apes breached the tower using a hijacked tank and imprisoned the humans while Dreyfus, the leader of the remaining human survivors, fled underground. Malcolm's group transports Caesar to his former home in the city where they learn of his past with humans. Malcolm leaves the group and heads into the city to find medical supplies for Caesar. Eventually, Malcolm returns with the medical supplies and Blue Eyes who had encountered Malcolm whilst he was searching for the medical supplies. Blue Eyes is overjoyed to see that his father is alive and stays by his side while Ellie prepares to operate. After the surgery, Blue Eyes also learns of his father's past with humans before Caesar suddenly awakens. Blue Eyes apologizes to his father, but Caesar tells his son that it is his fault and that he shouldn't have trusted Koba. Because of Koba's actions, Caesar realizes that apes can be as violent as humans. Blue Eyes informs his father that Koba imprisoned the apes still loyal to him and that Koba killed Ash, much to his sadness. Blue Eyes tries to reassure his father that once the apes see that he is alive, they'll turn from Koba, but not if Caesar is weak. Since ape always seek the strongest branch. Unable to contain his rage towards Koba for not only his betrayal, but for what he is trying to turn his people into, Caesar is determined to try and stop Koba, but is in no condition to fight just yet. Therefore, Blue Eyes, speaking in broken English for the first time, asks his father to let him help him. Caesar, proud of his son, agrees.
Two days later, Caesar, slowly recovering from the surgery, explores his former home and discovers an old camcorder, which depicts Will Rodman, Caesar's adoptive father, teaching a younger Caesar before Caesar is interrupted by Malcolm. Suddenly, Caesar spots, outside of his attic window, Blue Eyes, who has successfully freed the imprisoned apes, he had also successfully freed the imprisoned humans as well. Blue Eyes informs his father that Koba is planning to move the females and the infants from the forest into the city, including Cornelia and Milo. Fearing for his wife and his youngest son, Caesar urges Malcolm that they must leave immediately. Malcolm guides Caesar and the apes to the tower from below, but are forced to separate after encountering an armed human. Caesar and the apes climb the tower to the top where Caesar confronts Koba. Caesar and Koba battle for supremacy while the rest of the tribe watches on with concern. As Caesar and Koba's battle escalates, Dreyfus detonates C-4 charges that he planted beneath the tower. The resulting explosion kills him and collapses part of the tower. While Caesar and Blue Eyes help injured apes, a furious Koba suddenly begins to open fire on them, injuring Maurice in the process. Caesar then dives at Koba and tackles him, causing both of them to tumble down the debris. Caesar lands safely, but Koba is hanging over the edge of the tower. Pleading for his life, Koba reminds Caesar that apes do not kill apes, but Caesar states that Koba is not an ape anymore and lets him fall to his death, shedding a single tear at the latter's death. The tribe celebrates Caesar's victory.
After ending Koba's tyranny, Caesar notices Grey and several other apes threatening Malcolm who had survived the earlier explosion and orders the apes to leave him. Malcolm informs Caesar of the impending arrival of human military reinforcements that Dreyfus' men had made radio contact with. Caesar tells Malcolm that the humans will never forgive the apes for the war that they have started and advises him to leave with his family for safety as the two of them acknowledge their friendship. Both of them lament the fact that peace could have been achieved if there wasn't any animosity existing between the apes and the humans. As Malcolm disappears, Caesar reunites with Cornelia and Milo and along with Blue Eyes, he embraces his family. He then stands before a kneeling mass of apes, awaiting the war to come.