A phone call in the middle of the night alerted Larry Dexxman to the death of his wife Penny's friend Stella. It seemed to be a simple mugging, but what should have been a straight forward investigation turns major when the bodies start to pile up. Initial enquiries reveal that Stella's past, and her present, were shrouded in mystery, and when the frequent trips that she took before her death lead to the Department of Work and Pensions whose office in London is unaccountably destroyed in an explosion, the puzzle deepens. The investigation moves to Stella's last employer, Bytesize Systems Ltd, who were contracted to develop an AI solution for the DWP, but before any progress can be made, the owner is brutally murdered in a hit and run. Larry, despairing that he will ever get a handle on the puzzle is not as surprised as he should have been when the whole thing is brought to a head by his home being invaded by armed intruders.