Staying in a rural Guest House (along with Nigel Strangeways and his ) is a scientist Wragby, whose formula could be a major breakthrough, his second life Elena, and Wragby's own Lucy, an engagingly enterprising 8 year old. Lucy is ""borrowed"" by some Russians with the hope of securing Wragby's formula in return; her betrayal to them reveals an unexpected collaborator; but her rescue is due primarily to her own observant and resourceful interference... An old hand, still imber, in an orthodox but genial story.