As DI Hudson's new investigation unearths serious flaws in the original murder investigation, those who were closest to Tara are forced to explain away credible motives for wanting to kill her. Relationships are strained to breaking and damaging accusations fly when David confronts his brother and sister-in-law over access to his children.

• Chris Lang
• Matthew Arlidge

• Lee Ingleby
• Hermione Norris
• Daniel Ryan