Tina Rossi, the world's leading coloratura soprano, has travelled to Edinburgh, ostensibly to sing in the Festival,  in reality to meet her lover, top scientist Kenneth Holmes. But instead of finding Kenneth at their rendezvous, she discovers an unknown corpse.

Enter Johnson Johnson, a famous but enigmatic portrait painter whose yacht Dolly is about to sail in a race to the Hebrides where Holmes was conducting his top-secret research.

Soon Tina and Johnson are sailing the high seas  to investigate Holmes' disappearance, but as Dolly nears Rum, the race has become one for life rather than prize money...