There's been another murder in Successville. This week D.I. Sleet is joined by sports pundit Chris Kamara, who takes on the role of his cop sidekick.

They discover that D.I Sleet's close friend, Successville's most successful race horse, Alan Shearer has been murdered. Tom Daley, the horse's jockey is mourning at the local stables when Sleet and Kamara turn up looking for clues. Tom Daley reveals that he was bribed to lose the race by John Bishop, but Alan refused, costing him his life.

Kamara is put through his paces as he and Sleet meet three suspects:

Sport's Promoter John Bishop - Bishop was angry that his fixed race had failed. Was he livid enough to become a murderer? Who else was involved in the betting ring?

Cara Delevingne - Sleet finds out from John Bishop that Cara was involved in the failed fixed race, so he brings her into the station for questioning. But can Kamara handle the feisty suspect?

Sheikh Kayne West - The owner of the horse that was supposed to finish first. So was he such a bad loser that he killed Alan Shearer? Kamara goes undercover as a prostitute to find out?

After meeting all three suspects, it's time for Chris Kamara to decide - who killed racehorse Alan Shearer? As ever in Successville it's a matter of life and death as Chris attempts to catch a killer. Have you been paying attention? Did you spot enough clues to work out who the killer was?