- "And as for Caesar, kneel down, kneel down and wonder."
- ―Charles quotes Shakespeare to infant Caesar.
Charles Rodman was the father of the late Will Rodman, and the adoptive human grandfather of Caesar. Ten years after his death, he would become the late adoptive human great-grandfather of Caesar's two young sons, Blue Eyes and Cornelius.
Suffering From Alzheimer's
Once a talented pianist and professional music teacher who earned a honorary certificate, Charles began to suffer from Alzheimer's Disease, which his son (either through coincidence or design) researched a cure for at the Gen-Sys Laboratories. He had been cared for during his illness by a nurse named Irena, who couldn't stand Charles' behavior due to Alzheimer's Disease and wished that he would leave the house to stay at a shelter.
Adopting Caesar and Temporary Recovery From Ailment
Although trials of the "ALZ-112" were called off, Will secretly stole canisters of the drug and adopted the baby chimpanzee that Charles named Caesar, who had been exposed to the drug via the embryo. Three years later, noticing its effects on Caesar, he administered the drug to Charles, who immediately recovered his mental abilities and was once again able to play the piano. For five years they lived a happy life, with Charles taking care of Caesar when the chimpanzee was a newborn.
Relapse of Disease
Charles was on bad terms with his neighbor Douglas Hunsiker on two occasions. The first time was when Hunsiker used a baseball bat in an attempt to strike Caesar when he entered his garage to ride a bicycle, with Charles stating, "He just wanted to play". The second and worst time was when Charles, having become immune to the drug and suffering once again from Alzheimer's, got into Hunsiker's car and tried to drive it, damaging the front and back of the car by bumping into the cars it was parked between. Hunsiker grabbed Charles out of his car and decided to get out his phone to call the police. Charles tried to grab the cell phone away from Hunsiker. Caesar saw the situation through a window and although not aware of why Hunsiker was angry at Charles, was aware that his grandfather figure was being threatened. To save him, Caesar attacked Hunsiker refusing to let him run off to his house. After Caesar bit Hunsiker's finger off, Charles yelled at Caesar to stop. Their last moment together was when Caesar and Charles hugged each other, fearing what consequences awaited Caesar.
After Ceasar's incarceration, Charles' condition continued to deteriorate. Later, Will tried to test the ALZ-113 on Charles, but he refused and died the next morning from Alzheimer's. It is unknown if Charles had some suspicions of the devastating effects ALZ-113 has on humans, or if he figured it was his son's time to let him die naturally.
Despite his Alzheimer's, Charles was a kind-hearted man who greatly loved his only son, Will. He immediately took a liking to the baby chimpanzee he and Will later named Caesar and said a seemingly prophetic line from Caesar's namesake, Shakespeare's Julius Caesar text. He came to think of Caroline as a daughter and Caesar as a grandson as shown when visibly he was distraught when Caesar was taken away and placed in the primate shelter.
- An earlier version of the script used the character name "Walter Rodman", who had earned diplomas in physics and astronomy in his younger days. In his state of confusion, Walter often addresses Will as "John", but Will reminds him that "John is gone". After Walter's death, Will looks at an old photo showing Walter with two teenage sons.
- It is possible that the character's name, and medical condition, may be a homage to Charlton Heston, the original lead actor in the Planet of the Apes universe, who was also diagnosed with Alzheimer's disease several years before his death.
- It is likely that Charles never got to see Caesar before his death as he is not mentioned after he dies. It is also unknown whether Will told Caesar that Charles had died.
- Christopher Walken, Tim Conway and Robert Englund were considered for the role of Charles.