Nightmares delves into the innermost fears of the Scooby Gang, revealing whole new layers of their personality in the process. But what is it that these fearless vampire killers are most afraid of?

Xander is most concerned that he'll be humiliated by turning up for class in his boxer shorts. On the plus side, he gets to eat a huge amount of chocolate before facing a scary clown from his childhood. Willow is petrified of performing as the world's finest soprano.

Buffy, unsurprisingly, fears that she'll do badly in her exams and that she'll become one of the creatures she most hates. It's a nice idea, but is soon thrown away.

By far the best scenes are those between Buffy and her estranged father, Hank. It may be manipulative, but it's hard not to be affected by scenes which pare away at one of the few normal relationships that Buffy has.

The episode is not as dark as it might have been. It's brightened by Willow's stage appearance, which is one of the funniest scenes of the series. Another highlight has to be Cordelia's extremely bad hair day - made worse by her enforced visit to the school's chess club.

David Greenwalt's script, from a story by Joss Whedon, provides a rugged framework, bonding together the various set-pieces, which otherwise might have seemed rather inconsequential.