I’d like to believe that with Vincent Price films, what you see is intended to be taken literally, without a hint of irony or camp. Thus it is that we are expected to recoil in horror as Doctor Rappaccini, played by Price himself in his Twice-Told Tales (USA, 1963) injects a guinea pig with a poisonous concoction.
So far so good—lots of smoke and a twitching guinea pig model. Convincingly scary as a concept played with a bit of subtlety. But then, alas, it turns purple.
See, because it was poisoned, it turned…oh, nevermind.
With any luck, once you stop laughing you’ll turn to the source material for this portion of Twice-Told Tales, “Rappaccini’s Daughter” by Nathaniel Hawthorne. Not much laughter there, and also no guinea pig.