Still mourning the loss of Pc Emma Keane, Sergeant Stone throws himself back into his work, telling his officers that he will find the bomber, who is still at large. But Sun Hill is horrified to receive another message warning that another bomb will explode in three hours’ time.

After DC Grace Dasari quizzes Carl Adams and Jeff Bowman, who were targeted in the previous blasts, the officers are shocked to learn that Emma’s murderer has been in the station all day and has now disappeared. The ticking bomb is eventually traced to a Mrs Waverley, who is doing the school run, unaware of the tragedy about to unfold.

With just seconds to spare, Stone and DC Mickey Webb find Mrs Waverley outside the school, and Stone orders Mickey to get Mrs Waverley to safety while he tries to get the baby out of the car. A helpless Mickey watches as the car explodes – but there’s no sign of Stone or the baby…

Later, Emma’s funeral is held, and Sun Hill officers bid a farewell salute to their much-loved colleague.

VIDEO: Watch an explosive clip from this episode of The Bill.