Director-writer M Night Shyamalan brings his distinctive, oblique approach to aliens in Signs after tackling ghosts (The Sixth Sense) and superheroes (Unbreakable). With Mel Gibson replacing Bruce Willis as the traditional Shyamalan hero--a family man traumatised by loss--and leaving urban Philadelphia for the Pennsylvania sticks, the film starts with crop circles showing up on the property Gibson shares with his ex-ballplayer brother (Joaquin Phoenix) and his two troubled pre-teen kids (pay attention--all these character quirks turn out to be important). Though the world outside is undergoing a crisis of Independence Day-sized proportions, Shyamalan limits the focus to this family, who retreat into their cellar when "intruders" arrive from lights in the sky and set out to "harvest" them.

Just as Unbreakable slowly revealed itself to be Superman re-thought as an intense personal drama, this is The Birds redone as a religious drama of faith lost and perhaps regained. The tone is less certain than the earlier films--some of the laughs seem unintentional and Gibson's performance isn't quite on a level with Willis's commitment--but Shyamalan still directs the suspense and shock dramas better than anyone else.

On the DVD: Signs has THX-certified Dolby Digital Surround Sound which reproduces in the home exactly as the scary sounds that creeped you out in the cinema. A selection of deleted scenes are mostly tiny, but there's a self-reflexive joke (wisely dropped but worth preserving) as Gibson wishes his dead wife were here in the crisis because she was so smart: "She always knew how movies would end." A six-part making-of goes deeper than the usual puff-piece, including an interesting alternative to a commentary track as Shyamalan talks through a précis of clips and on-set snippets. A tradition continued from the Sixth Sense and Unbreakable DVDs is an extract from Pictures, "Night's first alien film". It's a teenage camcorder effort in which the future A-list Hollywoodian is menaced by a tiny Halloween-masked robot. Also included are a "multi-angle storyboards" feature, subtitles in a clutch of languages and eerie menu screens. --Kim Newman

A family living on a farm finds mysterious crop circles in their fields which suggests something more frightening to come.