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Series 4 (2013)

Unlike the previous series's, broadcast on Wednesdays at 9pm instead of Mondays at 9pm. Kept series 3's format of 3 lots of two episode cases.

Case One (Part 1)
Chandler, Miles and the team cross paths with MI6 as they investigate the gruesome murder of an apparent tramp. The murder, they discover, is a 16th-century torture, the peine forte et dure. 
Directed by: Jon East |  Written by: Ben Court & Caroline Ip | Airdate: 4 September 2013
Case One (Part 2)
As the witch-hunt continues, with two corpses (the second burnt at the stake) in the morgue and a third person missing, the team must save the next victim and catch the killer, who they realize has ergot poisoning.
 Written by: Ben Court & Caroline Ip | Airdate: 11 September 2013


Case Two (Part 1)
The discovery of a flayed face in a Whitechapel gallery leads Chandler and Miles into the art world - but is there also a link to organised crime?  
 Written by: Steve Pemberton | Airdate: 18 September 2013
Case Two (Part 2)
As more flayed bodies turn up, Chandler and Miles question the motives behind these bloody deeds. Buchan's research puts him in danger.
 Written by: Steve Pemberton | Airdate: 25 September 2013

Case Three (Part 1)
The team are in a shambles and Buchan is still traumatised from the previous case. After a body is found in a sewer the team riducle Buchan's ideas of a serial killer but as the case progresses he might not be far wrong. more
 Written by: Ben Court & Caroline Ip | Airdate: 2 October 2013
Case Three (Part 2)
The tension mounts as the source of the office haunting and the shadowy figure that taunts Miles is revealled. The team closes in on a mysterious eating club as more victims are harvested and Chandler fears that if the killers can't be caught in time a lot more people might die.
 Written by: Ben Court & Caroline Ip | Airdate: 9 October 2013

Guest & Recurring cast: