Recently promoted to CID, D.C. Carver is feeling seasick while he and D.S. Roach work on a case on the police launch. The River Police fish the body of a murdered informant out of the Thames, but Roach is furious when the case is taken over by two detectives from Scotland Yard. P.C. Taffy Edwards and Stamp attend an incident with an unconcious elderly man who has a very protective dog. A woman offers to help, but Stamp tells her to move along. Stamp is horrified when the woman arrives at Sun Hill as the new uniformed Inspector, Christine Frazer. P.C. Hollis is running a sweep on who D.I. Galloway's replacement will be - there are rumours it will be D.I. Burnside. At the hospital, a solid gold krugerand is found on the old man, and W.P.C. Ackland and D.C. Carver realise the body in the river is the old man's nephew, who was grassing on his accomplices in a krugerand robbery. Sgt. Penny is back at work on light duties, but he is clearly still deeply affected by his recent shooting.