A woman engages Caroline to stay for three days in her cottage in Sussex and post daily pre-written postcards to her husband at home. Caroline and Sylvia are dubious about getting involved but they need the money.
They gain her assurance that nothing illegal is involved and promise not to draw attention to themselves.
It will be a well-paid long weekend away.

Sylvia does manage to draw attention when she is rescued from the sea by a Lifeguard. Although, as she points out, that was hardly her fault since she was not drowning but waving.

At the end of three relaxing days, they begin the drive home and Sylvia gets a message on her Blackberry.