At last a leading role for Scottish actress Shirley Henderson, playing a factory worker still haunted by the disappearance of her sister two years earlier. The debut feature of writer/director Juliet McKoen, Frozen shifts between the real and the imagined, and benefits from an atmospheric sense of place - the setting is a deprived fishing community in and around Morecambe Bay. However the screenplay, with its underwritten male characters and overbearing symbolism, only fitfully convinces.

Partly inspired by the Lady in the Lake murder case, Frozen follows its diminutive central character Kath (Henderson) in her increasingly obsessive attempts to uncover the mystery of her sibling Annie's fate. In an echo of Antonioni's Blow Up, she becomes fixated on a piece of CCTV footage, taken on the night Annie was last seen, and she also experiences supernatural visions of an afterlife, witnessing her sister being rowed across the estuary by a stranger. (As her counsellor cum priest Noyen (Roshan Seth) points out, the ancient Greeks believed that to reach the afterlife, souls were ferried across a river of forgetfulness.)

"CHILLY IMAGERY"

Primarily shot on high-definition digital video, Frozen has a mood of timelessness, and is filled with chilly imagery, evoking its protagonist's internal impasse. But although Henderson conveys Kath's mixture of child-like fragility and emotional volatility, she lacks the raw intensity that Samantha Morton brought to Under The Skin and Morvern Callar. And whilst Noyen, the film's intermittent narrator, talks of "mysteries that are beyond human explanation", McKoen relies on a clichéd serial killer twist for her disappointing resolution.