Unforgotten's latest episode is out on Monday evening, and will bring us one step closer to the truth behind Matthew Walsh's murder 30 years ago. While there are four key suspects who were involved in his death, who do you think was the main culprit? Plenty of viewers have already taken to Twitter to discuss their theories, so check out some of the most interesting ones here...
Posting on the social media site, one person suggested: "Three eps into #Unforgotten and there are reasons to suspect all four main characters. Am sure they all conspired with the hiding of the body. But was Fiona assaulted by Walsh and the others helped her get rid of him? Ram seems too much of a baddie - must be more to him."
WATCH: Have you been watching Unforgotten season four?
Another viewer also suggested that they thought Ram was a key character behind the murder, writing: "I think Siduh has more to hide, has he covered something up to not want to give an interview? He hasn't put himself in a good light there. And who has he been in contact with, to just say, 'It's me, we need to meet' on the payphone?? He's hiding the most!"
Who was behind the murder?
Another fan suggested that the late Carl Fogerty, whose freezer contained Walsh's body, is actually still alive, writing: "Fogerty is still alive, living under a different name, that's who they\ve been contacting. Are they all being blackmailed by him? Doing what he says?"
There are four key suspects
Meanwhile, one fan tweeted that the body parts found in the storage unit could be down to all of the suspects together, writing: "Current theory: they had just come from a party full of booze and pills, the victim had taken something and had a bad trip and went running, came out of the woods and got knocked by the car accidentally. The others freaked and covered it up." What do you think happened?
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