Spa thriller

A gaggle of twenty-something girls heading on some kind of hen-style spa trip in Bath. They have to pretend not to know each other when they go into the venue, because if they declare themselves as a group, they’re restricted to certain time slots and activities. So mum’s the word. They can meet up “airside” once they’ve got through the security. One of them has brought along some horror movies for them to enjoy on DVD tonight. Evil Dead and Halloween 25, she says.