Pat is forced to reinvestigate other lines of enquiry, while Mike finds himself trying to cover his own backside when evidence reveals that a psychic was used in an attempt to uncover evidence relating to the case.
When young mother Susan Harrow fails to return home after a night out, her mother reports her missing to the police.Her body is later found on wasteground near to where she disappeared.However, due to special programming regarding the September 11 attacks, the programme was removed from the schedule and was not rescheduled for broadcast until June 2002.Certain other territories, including Australia, still received the broadcast in 2001.Meanwhile, Walker has worries of his own, as his ex-wife Lyn is dating an abusive, unstable man, Eric Fowler (Tim Mc Innerny), who turns into a manic-obsessive when she decides to leave him.
A severed female hand is found in the outreaches of Thames, which brings Róisín into contact with old friend Mike, who is now back in uniform after being found innocent at his murder trial.
When Morton's accomplice confesses to murder, Walker is suspicious.
Fifteen-year-old Cassie Booth goes missing whilst doing her local paper round, and her blood-stained clothes are later found in a nearby boathouse during a police search.
David Hayman stars as the main protagonist of the series, DCS Michael "Mike" Walker.
Throughout the series, he has two main sidekicks: DI Pat North (Kate Buffery) and DCI Róisín Connor (Victoria Smurfit).
Pat is asked to investigate a fifteen-year-old case in which Gary Meadows (Steven Hartley) was murdered by his boyfriend, James Mc Cready (James Wilby), a case which was originally investigated by Mike.