Sam's Mum So Fat

Alright listen up, genius. The joke is that Sam's mum is so fat that when she fell down the stairs, the person telling the joke thought the credits for the British TV show EastEnders was showing. EastEnders has an opening sequence where the camera pans over the River Thames and shows the city of London. In the sequence, the camera lingers over the houses, and then the drums kick in, and the credits roll. Get it now, dumbo?