In the final moments of Sherwood episode 2, there's a jaw-dropping development that many viewers won't have seen coming – and it all started with a visit from a delivery man.

A package for the newly-married Sarah and Neel was dropped at Andy's house, which he later carried over to theirs. He let himself in, as he's prone to do, where he was met by a furious Sarah. Thinking she was home alone, she had been sat on the toilet with the door open, which led to a very awkward encounter between herself and her father-in-law.

With Andy away on business, there was no one to act as a buffer between them and their exchange escalated, with Sarah bemoaning Andy's presence in her life. She then went on to make several cutting remarks about Andy's relationship with his late wife – the last words ever spoken by Sarah.

Andy, seeing red, picked up one of her freshly unboxed garden tools and smacked Sarah round the head with it, killing his son's wife on impact.

He stood there before her lifeless body as a pool of blood began to form around her head, before the scene faded to black and the jaunty folk music kicked in.

Joanne Froggatt (Sarah). House Productions/Neil Sherwood BBC

Sarah joins Gary Jackson, an ex-miner who was also murdered on his walk home from a drinking session at the local working men's club. Scott Rowley, with his impressive archery skills, is the prime suspect, but Dean Simmonds has also got good aim, and a motive.

Another focus of the BBC drama is the identity of the undercover police officer who infiltrated the Nottinghamshire community and remains to this day.

Speaking to Radio Times magazine, David Morrissey, who plays DCS Ian St Clair, said: "We've seen undercover operations within criminal and terrorist organisations in dramas like Line of Duty, but the idea that there were undercover officers inside legal organisations eavesdropping on conversations, feeding back information and sometimes having relationships with people without telling them who they really were, is outrageous.

"And it's something that we need to really look at, right here, right now."

Sherwood continues on Monday 20th June on BBC One at 9pm. Check out our Drama hub for more news, interviews and features or find something to watch with our TV guide.

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