Awesome Music: Creedence Clearwater Revival's "Bad Moon Rising" makes a huge impression, somehow, despite the fact that not much really happens while it is playing. (The great transformation scene does not take place to this tune, but to Sam Cooke's version of "Blue Moon.") Also, Elmer Bernstein composed about eleven minutes of music for the film, which was so good that the technoband Meco based an entire album on it.
Idiot Plot: If David and Jack has just stayed on the road as they were told to do several times, instead of deciding to travel across the moors at night, they wouldn't have been attacked by the werewolf and the rest of the plot wouldn't have happened.
That was more a case of them not realizing that they had left the road then them simply neglecting the warnings. Besides, it's not as if werewolves can't cross roads.
Narm: For some, the ironically upbeat songs picked for the soundtrack kinda ruin the moments they accompany. A YouTube commenter once remarked on a clip of the transformation scene they nearly left the page because they thought the clip, featuring David's horrific transformation accompanied by jazzy, romantic crooning, was a parody.
The policeman in Trafalgar Square who successfully manages to ignore David's volley of swear words is played by Peter Ellis, who only a few years later went on to play the regular character Chief Superintendent Charles Brownlow in British long-runner The Bill.
Rik Mayall plays a patron at The Slaughtered Lamb.