Justice League Unlimited

S03E08 The Great Brain Robbery

A powerful mystical object leads to an unexpected body swap between Lex Luthor and the Flash. As they navigate their new realities, Lex struggles to adapt to the speedster's abilities, while the Flash faces the daunting intellect and cunning of Luthor. Their identities clash as each tries to leverage the other's strengths for their own agendas, creating chaos and challenging their understanding of power and morality.