As the re-investigation into the 2007 murder of Grant Hill gets underway, policeman Rob Hollins quizzes his colleague DI Mark Addison about the original case.

Addison is convinced Grant’s widow Charlotte is guilty and should have stayed in prison. But Rob argues Charlotte had no motive for wanting to kill Grant.

As Rob digs further into the case with new Task Force boss DCI Joyce Ordega, he suggests Dr Emma Reid and surgery receptionist Valerie Pitman from The Mill might be able to help, as they worked with Grant shortly before the murder.

But Rob’s in for a surprise when Joyce recognises Valerie’s name as she’s sure Valerie was somehow connected with the original investigation…

Meanwhile, Charlotte Hill is a free woman again after having her conviction for murder overturned. But what’s she doing down at The Mill and why does she want an appointment with Dr Sid Vere? Unaware of her possible killer past, Sid agrees to help.

Elsewhere, things are getting no better for Al Haskey following the online backlash over his radio interview about his clash with tourist bus driver, Mr Singh.

Both Dr Jimmi Clay and practice manager Becky Clarke think Al should apologise to Mr Singh for his comments (and also consider an anger management course!). But will stubborn Al do the right thing and hopefully save his reputation at the same time?

Doctors, Pat Dyson, Esther Milne, Greg Milne, Valerie Pitman

Valerie is caught-up in the marriage troubles of Esther and Greg (Picture: BBC)

Also in Letherbridge, Valerie Pitman finds herself caught up in a mystery involving Esther Milne, who wants to get away from her overbearing husband Greg and a series of newsagent robberies by a hooded figure wearing a plastic dog mask!

Doctors continues weekdays at 1:45pm and 5:30pm on BBC One