First broadcast 1/2 August, 2004.
Boyd attends anger management sessions whilst simultaneously, with the team, investigating a murder which is connected by the pistol used to many other killings stretching back decades.
Notable guest stars: Nigel Terry, TP McKenna.
The one where… Boyd learns to quote The Tempest when he’s stressed… and then gets punched in the face.
First broadcast 8/9 August, 2004.
Boyd’s team combine with another police unit to search for a serial killer who carves the word “sorry” into the backs of his victims.
Notable guest stars: Phil Daniels, Julian Glover, Emma Fielding, James Dreyfus.
The one where… Grace quietly seethes when Boyd takes a shine to the other team’s (younger) offender profiler.
First broadcast 2/3 October, 2005.
The discovery of two bodies leads the team to a man whose entire life is built on deception and pretence.
Notable guest stars: Toby Stephens, Nicola Stephenson, Ronan Vibert.
The one where… an inadequate man pretends to be something he’s not and hides out in an allotment shed. And nothing much else happens.
First broadcast 9/10 October, 2005.
Grace’s past comes back to haunt her when Tony Greene launches an appeal against his murder conviction – the one she helped secure in the early days of her forensic career.
Notable guest stars: Tom Ellis, Paul Freeman, Angela Bruce.
The one where… the ’80s police investigation is shown in multiple flashbacks, significant details of Grace’s past are revealed including her affair with Harry Taylor, and the team receives a jar full of severed human fingers.
First broadcast 15/16 October, 2005.
Steven Hunt is a serial killer who enjoys drowning women… all Boyd and his team have to do is prove it.
Notable guest stars: Stephen Moyer.
The one where… Boyd half-drowns a suspect.
First broadcast 14/15 January, 2007.
Trying to avoid a diplomatic incident, the Foreign Office task the CCU with finding the skull of the Mahdi, which was taken as a war trophy in the 19th century. In a parallel investigation, the team try to identify the murderer of Omar Jaffiri, who was allegedly tortured on behalf of the British security services.
Notable guest stars: Graham Crowden.
The one where… everyone spends an awful lot of time looking at skulls.
First broadcast 18/19 February, 2007.
Boyd is sent a dagger from New York, which relates to a case Mel was looking into just before she died. As they investigate a murder from the ’40s, the team are temporarily joined by Sarah, a Mossad agent who tracks Nazi war criminals.
Notable guest stars: Michelle Forbes, Eileen Atkins.
The one where… the wartime plot is shown in black and white flashbacks, and Boyd gets romantically entangled with Sarah.