Jacob Montfield, regarded by the majority as a homeless eccentric, a nuisance by a few, had pushed a supermarket trolley around the city for years.

However, one person regards him as a liability.

Eccentric was correct, a nuisance, for sure, mad, plenty thought that, but few knew the truth, that Montfield is a brilliant man, once a research scientist.

And even less knew that detailed within a notebook hidden deep in the trolley, there is a new approach to the guidance of weapons and satellites-a radical improvement on the previous and it's worth a lot to some, power to others, accolades to another.

And for that, one cold night, he died at the hand of another.

Inspector Tremayne and Sergeant Clare Yarwood are on the case, but so are others, and soon they're warned off. Only Tremayne doesn't listen, not when he's got his teeth into the investigation, and his sergeant, equally resolute, won't either. It's not only their careers on the line, but their lives.