 Having recently fallen in love with grad student and chemistry teacher Carla Purty (Jada Pinkett Smith), Klump uses his latest discovery, a weight-loss serum that rewrites the subject's genes, to lose weight in order to spend time with her.Unfortunately, this serum creates the confident but mean-spirited individual known as Buddy Love, due to the testosterone imbalance caused by the transformation causing Buddy to manifest as an independent personality.When Klump's student and assistant Jason learns what has happened, he realizes that Buddy is gaining increasingly greater freedom from the professor's influence.