Brassic's Michelle Keegan reveals blooper that was left in season 4

"We’re all dressed up as these characters and I found that hilarious," said Keegan, who plays Erin. "I've never done [a murder mystery] before, so for me, it was brand new. I had no idea what it was.

"But we had lots of fun doing that and I loved the fact that everyone got into character – Aaron [Heffernan], who plays Ash, started speaking with this really random accent... he never got told to do it, but he started trying to speak in this posh accent. It came out of nowhere, but it was just so good."

In fact, the cast enjoyed filming this episode so much that they struggled to keep a straight face on-camera – with Keegan revealing that one outtake has made it into the show. "You could see us laughing, as us, and they’ve left that in the edit. So if people watch the series, you can actually tell when there's an improvisation going on or someone’s added a line in [because] we’re naturally laughing."

"I think that's one of the things that people love about Brassic – that it is so infectiously funny, that you can't help but laugh because these guys are having such a good time," added Damien Molony, who plays Dylan. "They're so optimistic and they're so warm hearted.

"It’s a show about a gang of best mates who are sticking together when times are tough and trying to make a go of it and have a laugh while they do it. From speaking to people on the street, that's what they love about the show. Yes, there's lots of capers that go with it, but they only work because the gang is so tight."

It won't all be fun and games for the Brassic crew, though. Having seen off local gangster Terence McCann (Ramon Tikaram) at the close of the previous season, the gang have to go up against a new menace: the McDonagh brothers, a pair of unhinged crooks.

"There's something very, very scary about about the two of them," said Molony. "I think that unpredictability is a huge part of it. Every time we think 'Oh, maybe we can work with these guys', the rug gets pulled out from underneath us very, very quickly."

Those rug pulls will lead to some dramatic scenes this season – fans should definitely brace themselves – with Molony suggesting that, after four series together, the cast now find it easier to navigate the tone of Brassic, jumping from tragedy to slapstick comedy.

"We know our characters so well at this point that we can very quickly switch on any particular kind of emotion. Joe [Gilgun] talks about watching the rushes and we're all just chatting about the takeaway that we had the night before – then someone says 'Action!' and it's like a switch is flipped.

"The camaraderie and the the group dynamic adds to that storytelling in such a special way. We feel very lucky as actors to to have that."

Sky has confirmed a fifth season of Brassic is on the way before the fourth has even aired – and having started filming together back in 2018, Molony says the cast have "matured as actors in a way that we possibly haven't as characters".

"Series one, it was, 'Right, we're going out for drinks, we're going to this bar, we're gonna have a great night out in Manchester.' And now it's very much Sunday roasts and boutique cinema trips!"

Brassic 4, a Sky Original, starts Wednesday 7th September on Sky Max and NOW.

Catch up on all episodes of Brassic season 1 for free on YouTube.

Check out more of our Drama coverage or visit our TV Guide to see what’s on tonight.

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