Ex-journalist Tash has been searching for a story to launch her freelance career. But she has also been searching for something else. New friends to help her navigate motherhood. She sees them at her son's new playgroup. The other mothers. The sleek, the sophisticated, the successful mothers. The women she wants to be. And then one day they welcome her into their circle and Tash discovers the kind of life she has always dreamt of; their elegant London townhouses a far cry from her cramped basement flat and endless bills. These families seem to have everything. But they also have their secrets. And it's soon clear that not everyone at the playgroup can be trusted.