Grace - here's what to expect from the final episode in the Brighton-based detective series

John Simm has reprised his role as Detective Superintendent Roy Grace to huge viewing figures across the three-part series. Here are our reviews of the first two episodes – episode one and episode two.

Starring Richie Campbell as DS Glenn Branson, Zoë Tapper as Cleo Morey, Craig Parkinson as DS Norman Potting and Laura Elphinstone as DS Bella Moy, the new series has comprised three feature length films (3 x 120 mins). Dead Like You was directed by Camilla StrømHenriksen, Dead Man’s Grip by Isher Sahota and Not Dead Yet by Will Sinclair

In film three, this Sunday, Not Dead Yet, a rising music star, Gaia Lafayette, receives the opportunity of a lifetime, and the same night that she excitedly announces to her devoted fans that she and her band are headed to LA, a shocking turn of events leads Grace and Branson to believe someone may be trying to harm her. With a perpetrator on the loose, Roy must deduce who of Gaia’s fanbase may be concealing sinister intentions. Meanwhile, a grisly discovery on a remote Sussex pig farm puts Roy under serious pressure, forcing him to split his team in order to investigate two impossible lines of enquiry.

So far we have seen: FILM ONE – DEAD LIKE YOU. A chilling event at the Royal Edward hotel on the night of Assistant Chief Constable, Alison Vosper’s leaving do forces Grace and Branson into a difficult position when they must investigate all hotel guests, including high ranking East Sussex police attendees. Something about the incident is causing a deep unease in Grace - he knows he’s seen this before. Has a sinister offender from Grace’s past dubbed the Brighton Prowler resurfaced or is this a copycat? As the attacks continue, Grace is convinced it’s the same man – and delving into the past may be the key to saving the next victim.

FILM TWO – DEAD MAN’S GRIP. Grace and his team are called to the site of a tragic road traffic collision involving three vehicles: an articulated lorry, a car and a blue pickup truck. An unexpected discovery at the scene, found on the victim, soon suggests there could be far more to this particular accident than meets the eye, sparking an unsettling chain of events which leads Grace and Branson on a tense, desperate game of cat and mouse through the city of Brighton to save an innocent life before time runs out.

Episodes one and three (Dead Like You, Not Dead Yet) are written by Ben Court and Caroline Ip, with Ed Whitmore writing the second film (Dead Man’s Grip).

CHARACTER CREDITS: DS Roy Grace JOHN SIMM; DS Glenn Branson RICHIE CAMPBELL; DS Norman Potting CRAIG PARKINSON; DS Bella Moy LAURA ELPHINSTONE; Cleo Morey ZOE TAPPER; DS Nick Nicholl BRAD MORRISON; ACC Cassian Pewe SAM HOARE; Kevin Spinella ALEXANDER COBB; ACC Alison Vosper RAKIE AYOLA; Rachel Ryan HEATHER FOSTER; Johnny Kerridge THOMAS COOMBES; Mimi BONI ADELIYI; Rollo Mercer LUKE NORRIS; Mingo MAX KRUPSKI; Punt JAY OLIVER YIP; Badger ANDY APOLLO; Oliver Starling BEN WIGGINS; SOIT Officer CHARLOTTE WORKMAN; Jack Skerrit JACK PIERCE; DI Sid Barrow ROB JARVIS; Anna JO HERBERT; Roxy CHARLOTTE CHRISTOF; Detective Marcel Kullen ERNEST GROMOV; Sasha KIERA LESTER; Maggie JOANNA BROOKS; Dominic Pope NICHOLAS TIZZARD; Pippa Starling CLAUDIA JOLLY