When Shane is asked to follow the mystery trilling sound coming from the school corridor, he hopes that he can keep the phone that's making it. Shane has always wanted a mobile phone, but the last thing he expects is one that talks back! Mo is on the run from an alien planet and when Shane offers to mind her while she's on Earth he gets more than he'd bargained for. Mo is demanding, orders him about and won't keep quiet - if only she had an off switch! She does have one useful talent though - Mo can tell the future ...