Cast member Daniel Mays reckons the new season of Line of Duty will "take the show onto another level".
The award-winning BBC Two drama – where special police unit AC-12 investigate dodgy cops – sees Mays plays Danny Waldron, leader of an armed response unit, who becomes the latest officer under investigation.
"I think he's a character that will hopefully test people's perceptions," Mays told press on the Line of Duty set. "I don't want to reveal too much, but he has a great unpredictable essence to him.
"Certainly within the first episode alone, where it goes and what happens, it was just a barnstorming read.
"So if an ounce of that is realised on the screen, I think it will be a truly memorable first episode. It starts at a considerably high pace and doesn't let up.
"If the performances can match the standard of the writing and the production values, then hopefully we can take the show onto another level."
Line of Duty returns tomorrow (Thursday) night, on the back of two acclaimed performances from Lennie James - who played season one' antagonist Tony Gates - and Keeley Hawes, who was BAFTA-nominated for her turn last year as conflicted cop Lindsay Denton.
"Keeley knocked me out," said Mays, who worked alongside Hawes in BBC One's 2008-10 series Ashes to Ashes.
"What was amazing about that portrayal was that she stripped away all vanity and I thought without question it was her best performance - I thought she was absolutely spellbinding in that role.
"I'm well aware that I've got massive shoes to fill, because the pedigree is second-to-none. Not least with the core actors that you have - all of them are top-drawer - but specifically to follow Lennie and Keeley means a great deal."
Mays, though, will get his own version of the famous Line of Duty interrogation scene - a series staple that sees the investigated cop ruthlessly interrogated by AC-12.
"It's been the hardest thing I've ever had to learn," he said. "It's an incredibly ambitious piece of writing - not least to learn it, but then to make it dramatic and meaningful for the audience to watch. It's an amazing scene."
Line of Duty returns to BBC Two on Thursday (March 24) at 9pm.
