Pretty much a milestone in early 80's comedy – setting up two actors who'd lead two distinct streams of Hollywood comedy for years to come (Aykroyd with Ghostbusters and it's Saturday Night Live progeny and Murphy with the likes of Beverly Hills Cop). Also a fan favourite and with good reason – Aykroyd and Murphy are both very funny.

The fish out of water premise hadn't been as overused in those days, but here it's hammered to maximum effect as yuppie Louis (Aykroyd) is made to change places with down and out Billy Ray (Murphy) for a bet between Scrooge-like brothers Randolph and Mortimer Duke (Bellamy and Ameche). Various sub-themes like how money can't buy love, and how the rich elite use people as their pawns, but mostly owes it success to the chemistry and comic zing of Murphy and Aykroyd (although the underlying conclusion is that money is good, kids – the good guys end up with it all and the nasty villains with nothing). Famous for Jamie Lee Curtis' fantastic knockers as anything else.