This has been buggin me for years. Bear with me for a moment for a quickie plot synopsis then my real question:
One of the 1940s T&J cartoons, (I think it was called “The White Mouse”) involved a white mouse that had drunk some nitroglycerine (or something explosive) and escaped from a science laboratory. An all-points bulletin is issued, Tom is all panicky, Jerry paints himself white and fools Tom into thinking he is the white mouse. Tom spends the next several minutes saving Jerry from his efforts to blow himself up (typical cartoon hijinks ensue). The real white mouse shows up, Jerry’s ruse is uncovered (as is his natural color) - typical cartoon misunderstandings ensue and Tom smacks the white mouse whom he thinks is Jerry in disguise, causing the real white mouse to explode, creating havoc and destruction.
The very ending scene has the house blown to smitherines and the still-intact radio blaring that “the white mouse is completely harmless”. Tom rises slowly from the rubble, looks directly at the audience and says in an ultra-basso, monotone, drawn-out voice:
"Donnnnn’t yooooooou beeee-lieeeeeeeeve iiiiiiiiiit!!"
Apart from the fact that this cartoon scared the bejeesus out of me when I was very young, I know now that a lot of the cartoons of this era reference pop culture of the day (“Paging Mr. Ripley!”, “I’m only tweee and a half-years old!”, “I’ve been a baaaaad boy.”).
What in blazing tarnation is this sentence referencing?!? A famous catch phrase? A celebrity personality’s vocalization/delivery? What?! Help!