Malcolm Turner has been going undercover as "Big Momma". His teenage stepson Trent Pierce has just graduated from high school and is accepted into Duke University. However, he prefers to pass on college and pursue a music career as a rapper named "Prodi-G".
With his mother Sherry away on vacation, Trent tries to get Malcolm to sign a contract for him but Malcolm refuses as he believes that Trent should get his education. Persistent to get the signature, Trent stalks Malcolm while he is working on a case and witnesses a murder.