Because they've spent all their cash on booze during a night on the town, Dave and Eric have no money for a taxi home.

Dave has a drunken idea. "Let's steal a bus!"

He persuades Eric to break into the bus station. But 20 minutes later, Eric has failed to emerge.

Dave sticks his head round the door. "What on earth are you doing?"

"I can't find a number seven anywhere," says a distressed Eric.

"You idiot," shouts Dave, shaking his head in disbelief. "Just steal a number nine. We can get off at the roundabout and walk the rest of the way."