In this scene "Roger" challenges himself to name a movie for every letter of the alphabet. If he can't name one or pauses too long he has to do a messy forfeit. The game goes on till the mess runs out. "Roger" has:

Three custard and cream pies

One custard and shaving foam pie

A bowl of cake batter

A carton of custard

Pink Natrasol gunge

Blue methylcellulose gunge

He is wearing a black and yellow Fred Perry polo shirt and Under Armour Lycra compression shorts. It turns out he isn't as good at the game as he thought he would be and ends up getting very, very messy.