An American backpacker is mauled by a werewolf on the Yorkshire moors, turning into a beast himself while he convalesces in London with Jenny Agutter's friendly nurse.
A marvellous, pop tragic, serio-comic monster movie, with David Naughton haunted by the chewed-up ghost of Griffin Dunne as he tries to cope with the curse of the werewolf. The pre-CGI set-piece metamorphoses - as Naughton elongates and distorts into lupine form, sprouting hair, teeth and claws - are still amazing.
Writer/director John Landis also throws in American observations on British strangeness (from the unfriendly patrons in the Slaughtered Lamb pub to the dreariness of channel-hopping with three choices), a memorable shower sequence with Jenny Agutter, nightmare Nazis, pointed barbs at the expense of horror film conventions like silver bullets, and a witty assemblage of moon-themed songs (Blue Moon, Bad Moon Rising, Moondance).
Carnivorous lunar activities rarely come any more entertaining than this.