Deep in the Cambridgeshire fens, Laura is living alone with her 12-year-old daughter Beth, in the old tollhouse known as Ninepins. She's in the habit of renting out the pumphouse, once a fen drainage station, to students; but this year she's been persuaded to take in 18-year-old Willow, a care-leaver with a dubious past. Is Willow dangerous or just vulnerable? Is it possible she was once guilty of arson? Her mother's hippy life is gradually revealed as something more sinister; and Beth is in trouble as shcool and out of it. Laura's carefully ordered world seems to be getting out of control.