It is hard to make me laugh out loud, and few TV shows manage the feat. Supernatural takes the prize for making me burst out laughing, at times so hard I have spilled my drink. I just love the wacky, irreverent humour. No other show gives me unicorns shooting rainbows out of its ass, or suicidal porn-addicted giant teddy bears, or Sam the Knightrider car. There are so many examples of how they have pushed humour to incredible limits, and yet made it all believable in the Supernatural world.
And I just love that they fill every nook and cranny with humour. Every aspect of an episode like this is pumped full of colour and comedy, from the multicolour glitter goo of the title card, to the tiki-themed motel room, to the 24-style countdown and the "Right Friggin' Now, to the recreation of the iconic Jaws scene in a ball pit with a land shark, to the 70s cop show music during the foot chase with the lion mascot. From set dcor to sound track, they pay attention to every detail to make it all as fun as possible. And man, was it fun!
A big part of the comedy in this episode was watching fearless 6-foot-5, 220-pound Sam in varied states of anxiety, fear and terror as he dealt with his phobia of clowns. (And that's the thing about phobias, they are completely irrational and overpowering and can turn even the bravest and toughest into quivering puddles of anguish.) Jared's myriad facial expressions here are a sight to see, he has really stepped it up on the comedy front, and those mobile facial muscles are his biggest asset.
For his part, Jensen excels at physical comedy and comedic timing. He tends to use his whole physicality. My favourite example is what I dubbed the "full-body WTF" in What Is and What Should Never Be, after he wakes up back in Lawrence next to a girlfriend he has no memory of. As soon as she turns her back, he wildly looks around and his whole body staggers. There's another example in this episode, when he sees Sam covered in glitter and he does this full-body laugh.
I also have to single out the writing of this episode. Andrew Dabb and Daniel Loflin really hit it out of the park, they wrote a funny, wacky episode to rival Ben Edlund at his very best.