[last lines]
Radio Announcer: Your attention please! We have just learned from laboratory officials that the explosive contained in the white mouse is no longer dangerous. And they have assured us the mouse will not explode.
[Tom kicks the white mouse out the window only to have it explode reducing the house to rubble]
Radio Announcer: We repeat, the white mouse will not explode.
Tom: [emerging from the rubble and speaking very slow] Don't you believe it!