Singing in the shrouds

On a cold February night the police find the third corpse on the quayside in the Pool of London, her body covered with flower petals and pearls.

The killer walked away, singing. When the cargo ship, Cape Farewell, sets sail, she carries nine passengers, one of whom is known to be the murderer.

Which is why Superintendent Roderick Alleyn joins the ship at Portsmouth on the most difficult assignment of his professional career...