Episode five, which aired on Sunday 25 April, saw Kelly Macdonald’s Jo Davidson brought into the famous interrogation suite.
“These big interview scenes, the tension in them is unreal, not just because of the scene, but thinking, ‘Can we do this?’ – it’s 30 minutes long – can we get through it?’” Compston – who plays Steve Arnott – told the Shrine of Duty podcast.
He added: “Usually day two, after lunch, your mind has gone and you’re on autopilot. The giggles are ready to go as the finish line is in sight, it just takes something to go. Adrian [Dunbar, who plays Ted Hastings] had a bit of a brain freeze – but animal themed – and when he was on a rant at Kelly, he says a bunch of racist thugs, but it comes out as a slugs.
“There was a mountain of evidence, but he said there’s a mountain of elephants coming at you. And we were just like, what is going on?
“One of them happened and everyone’s averting their eyes and pinching their own legs under the table, trying not to laugh. The slugs one, everyone just lost it. That’s the horrible thing about the giggles, once you start, there’s no way back.”
Compston promised that fans will get some “big answers” during the finale this Sunday (2 May).
When quizzed on the identity of corrupt copper “H”, he said: “I wouldn’t quite go the Jo Davidson no comment route – but what I will tell you is I think there’s a lot of pay-offs coming this Sunday. There’s a lot of big answers and it’s deserved, people have stuck with us for a long time, so there comes a point where the story arch comes to an end.”
Compston also discussed whether there will be a seventh season. “We don’t know [if there will be another] – that’s nothing new. Jed always takes time after a series, like a couple of months. There’s a lot of stuff above my pay grade like analytics and audience scores. He takes the emotion out of it and looks at all that.”
He added: “It’s different this year, because we have to look it in terms of, do people want us back? 10 years in you start to think of legacy, and if it goes down that well it might be the perfect ending.”
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