Bewitched (1964)

S5E6 Mirror, Mirror on the Wall

In this episode, Endora casts a spell that transforms Darrin into an incredibly egotistical individual. Concerned that his newfound arrogance will jeopardize a crucial account with a prospective client, Darrin's worries seem valid. However, Samantha swoops in to rescue the situation by advising the client to focus on the youth demographic, turning the tide in their favor.