Catherine and Caroline, Toby and Mark were globetrotting siblings: British 'diplo-brats', whose childhood homes lay in Italy or Israel, France or Washington DC - wherever their father was posted at the time.

But all that was years ago. Now Catherine is approaching middle age, married to a life of cheeseparing selflessness looking after young offenders on a chilly organic farm; Mark is a prim supermarket executive, Caroline a wealthy Kensington wife, and Toby - well, Toby is a problem. The joker in the pack. He always was.

Amid growing tensions, marriage-fatigue and unspoken resentments, the apparent tragedy of Toby's mysterious disappearance jolts his sisters and brother into making angry anxious journeys: from California to Flanders, back in time and into their own hearts. The results are sometimes comic, unexpected, but oddly satisfying.