Writer-director Sean Ellis has very enjoyably expanded his prize-winning short film into an offbeat fantasy-comedy feature.

Art student Ben Willis (Sean Biggerstaff) is so distraught when his girlfriend leaves him that he falls victim to chronic insomnia. Resolving to make use of his extra eight hours of wakefulness, he goes to work the night shift at Sainsbury’s.

Ellis extracts a surprising amount of gentle comedy from Ben’s often surreal adventures, which are compounded by his ability to stop time at will, allowing him to move among his frozen fellow workers and the customers.

Ellis has a wry eye for character — the supermarket is populated by a variety of engagingly eccentric people that might well engender envy in, say, Ricky Gervais and Stephen Merchant of The Office fame — while his dry dialogue makes the most of the slender coming-of-age romantic narrative.

Biggerstaff and Emilia Fox’s checkout girl make credibly hesitant lovers and the oddball supporting players, headed by Stuart Goodman’s control freak manager, are excellent value. So, too, is the film.