Summary: There’s about to be another murder in Successville. This week D.I. Sleet is joined by TV personality Mark Wright, who takes on the role of his cop sidekick in this weird and wonderful world of improvised comedy.D.I. Sleet and Mark Wright are tasked with cleaning up the streets of Successville. Chief Ramsay wants them to eradicate a new lethal drug, nicknamed ‘Miranda’. The duo’s first port of call is to meet Daniel Radcliffe, a shady snitch, who has agreed to reveal the dealer responsible for the deadly drug. Unfortunately he is shot dead before exposing the truth. Looks like the detectives have a good old-fashioned murder mystery on their hands. Time to head to the seedier side of town to meet some dangerous Successville drug dealers.Mark quickly discovers that handsome good looks only get you so far in policing. The suspects the cop duo meet this week are:Biker Gang Leader Paul Hollywood. Mark has to go undercover to infiltrate a biker gang in an attempt to befriend their leader. Is Paul Hollywood capable of murder?Claudia Winkleman and Tess Daly. Two Successville residents that have fallen from grace through drug use and now live in a crack den. Can these two local druggies possibly have committed murder?Frankie Boyle. A cruel and psychotic cartel leader who clearly has no respect for the police. But is he crazy enough to have killed Radcliffe?Having met all the suspects, Mark must decide who shot Radcliffe and who had been peddling the drug Miranda on the street. Have you been paying attention? Did you spot enough clues to work out who the killer was?