Six army cadets on an all-night exercise in a deserted public school are troubled by ill-prepared heist men, the ghosts of old boys, and a simmering Satanic conspiracy that turns the posh, if ethnically diverse, students against each other. This low-budget British horror uses its school location effectively and there’s some decent character interplay, but it comes up light on spooks.
For most of the film, the resentful ex-squaddie book thief is more menacing than the glowing-eyed Fog-look spectres — only in the last act, when things get ritually nasty, does supernatural horror come to the fore.