Dylan Jones' new thriller is a wishy-washy stitching together of blatant Silence of the Lambs grisliness and generic US policer cliché. What it isn't is thrilling.

Briton Catrin Jacob has been murdered in the Chicago Planetarium and it falls to brother Rhys to come to the Windy City, identify her poor battered body. And meet the case cops: the sympathetic Susan Mackie, and her partner Lou Bek who couldn't give a fuck. Stamp it, file it, shitcan it.

Lou Bek, you see, has a schizophrenic brother called Jacob who sobbed incoherently down the phone the night his namesake died. The same brother who came home to their ageing mother sticky in someone else's blood. Bek has never covered-up on a case before - he won't - but he's not about to help anyone put his own flesh and blood away either.

Jacob is innocent. Jones tells us that much in the prologue. The real psycho is a whistling cab-driver with a houseload of boiled bones and medical textbooks. The book's supposed tension is designed into Bek's confusion, but since Dylan chooses to repeatedly shift focus between the cops and the bereaved, Unnatural Acts never builds up a head of steam. It perks up slightly when we see inside The Whistler's lair, but by then our interest is entirely prurient.

Characterless characterisation, lack-lustre romance and totally lacking feel for location, this is insipid as a thriller and entirely colourless as a piece of writing. *