To impress a beautiful girl, Harold Kelp, the grandson of professor Julius Kelp, who created a potion to transform his personality, gets his hands on his grandfather's secret elixir and unleashes his destructive alter ego, Jack.
Top Cast
Drake Bell as Harold Kelp
Jerry Lewis as Professor Julius Kelp
Tabitha St. Germain as Robin
Logan McPherson as Zeke
Jarrod Young as Begews
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