Conquest of the Planet of the ApesEdit
Lisa and Caesar meet first in a bookstore, where she is collecting a book for her owner, and then in the City's Command Center where both serve as slaves. Later, when Caesar launches an ape revolt, he makes a speech to the gathered apes (and a few captured humans, including Governor Breck and Mr. MacDonald), and condemns humanity. Lisa, heretofore mute, speaks for the first time, telling Caesar "No!" Listening to her, Caesar modifies his stand, telling the apes to leave their onetime human captors to their fate, and begin a world of their own.
Battle for the Planet of the ApesEdit
Many years after the end of Conquest, Caesar and Lisa are married, and have a son, named Cornelius after Caesar's own father Cornelius. Lisa is Caesar's counsel, who reminds him of his duties toward the other apes, and also of the humans now in his charge. She also discourages her son Cornelius from playing "war" with his friends.
After winning the battle when human mutants attack, Lisa supports Caesar's decision to free the humans who live with the apes, and try to live together with them as equals.