Spy vs. Spy

Black Spy's Dynamite Detonator (4x19)

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White Spy sneaks into Black Spy's house, steals his detonator, and tries to blow up Black Spy, but the detonator does not work. This is because Black Spy has a button on the "dynamite" that contains the real detonator which he pushes causing the real dynamite concealed inside of the "detonator" to blow White Spy to smithereens.