TV Guide Magazine by Matt Roush

It's a soul-crushing realistic depiction of the banality of evil. [7 - 20 Jun 2021, p.6]

The Independent by Ed Cumming

The question is whether the show’s any good. On the evidence of this frenetic, nerve-jangling opener: yes. After the more outlandish conspiratorial shenanigans of series five, the first episode of series six returns to what Line of Duty does best: dodgy coppers, tense action and characters who communicate almost exclusively in acronyms.

The Guardian by Lucy Mangan

As ever, nothing is wasted; not a scene, not a line, not a beat. For every morsel of information gathered by the team and by the viewer, another turn reveals 100 hidden possibilities. It fits together flawlessly.

Entertainment Weekly by Leah Greenblatt

Duty returns with a taut, screw-turning examination of an undercover officer gone rogue--the kind of slow-burn drama that earns your devotion. [17/24 May 2019, p.90]

The Hollywood Reporter by Tim Goodman

It still holds up as a compelling story, even if you're missing the myriad call-back references from the first four seasons. ... It's a testament to Mercurio that just when you think, "Well, this person is clearly guilty, as all the evidence suggests," he's got multiple switch-backs and loopholes to play with.

The Guardian by Sarah Hughes

Yes, there are times when Mercurio seems to want to be David Simon just a little too much – I'm going to put the line about "coming at the king" down to Lennie James' Tony Gates being a massive Omar fan in his secret inner life – but this first episode was taut, tightly scripted and well acted all round.

The New York Times by Alessandra Stanley

It’s a little like “The Shield,” the FX show that starred Michael Chiklis as a corrupt cop, but it’s a lot more like “Spiral,” the sleek French crime series on Netflix that has a cult following in Britain and the United States. So basically, “Line of Duty” is the opposite of “Downton Abbey,” except in certain elemental ways: an excellent cast, skillful writing and a knack for making an exotic, unfamiliar world seem like the viewer’s second home.

The A.V. Club by Sonia Saraiya

Line Of Duty makes an excellent effort at modern British life. It does fall short in places, but I give it a lot of credit for trying.

The New York Times by Mike Hale

If the new season falls slightly short of the show’s usual standard, it’s because neither this character (this season’s antagonist) nor the performance in the role is as interesting as its predecessors. Otherwise, all the elements are in place.