When Lucy insists that there's no such thing as luck, Brian is determined to prove her wrong. He purchases a pair of Josh's 'lucky' underpants and is delighted to immediately win a free pen and a pound. Josh decides to cash in on the phenomenon, and sells all the 'lucky' rubbish from his bedroom. He soon regrets the scheme when it leaves him jinxed. Brian discovers that his new pants will not bring him fame and fortune, so to save face with his sceptical family, he secretly buys his own prizes from a catalogue. Everyone is fooled, but Brian is about to find that pride comes before a fall.