Several generations in the future following Caesar's reign, apes are now the dominant species and live harmoniously while humans have been reduced to living in the shadows. As a new tyrannical ape leader builds his empire, one young ape undertakes a harrowing journey that will cause him to question all that he has known about the past and to make choices that will define a future for apes and humans alike.

An ordinary Lego mini-figure, mistakenly thought to be the extraordinary MasterBuilder, is recruited to join a quest to stop an evil Lego tyrant from conquering the universe.