Struggling with a new baby, Yvonne turns to netmammy, an online forum for mothers, for support. Drawn into a world of new friends, she spends increasing amounts of time online and volunteers more and more information about herself. When one of her new friends goes offline, Yvonne thinks something is wrong. But when the body of a young woman with striking similarities to Yvonne's missing friend is found, Yvonne realises that they're all in terrifying danger. Can she persuade Sergeant Claire Boyle, herself about to go on maternity leave, to take her fears seriously?