First broadcast 29th August 2011.

A website highlighting unexplained disappearances alerts the team to the death of young mechanic Christopher Collins seven years earlier.

Alun Armstrong ... Brian Lane
James Bolam ... Jack Halford
Amanda Redman ... Det. Supt. Sandra Pullman
Dennis Waterman ... Gerry Standing
Anthony Calf ... D.A.C. Strickland
Susan Jameson ... Esther Lane
Claudie Blakley ... Lisa Carlisle
Robert Daws ... John Carlisle
Adam G. Goodwin ... Jason Hibbert (as Adam G Goodwin)
Hayley Jayne Standing ... Alice West
Rufus Wright ... D.I. Mathew Hornby
Christopher Ellison ... Derek 'Smiley' Robinson (as Chris Ellison)
Nicholas Beveney ... Anthony Walters
Alex Lowe ... Andrew Hughes
Jonathan Aris ... David Crawley
Sheryl Gannaway ... Caroline Robinson