The Hollywood Reporter by Tim Goodman

Back is one of the funniest and most intriguingly different comedies in a long time. ... it's Blackwell's intelligent and searing writing--which also has quite a bit of emotional nuance--that makes Back much more than mere joke creation for its own sake. And it's Mitchell and Webb who make it all come to life, with Mitchell's virtuoso performance as the increasingly paranoid Stephen shining through all six episodes.

TV Guide Magazine by Matt Roush

Not-quite sibling rivalry hits new heights of hilarity in this second season of this savagely funny showcase for the British comedy duo of David Mitchell and Robert Webb. [12 - 25 Apr, p.11]

Entertainment Weekly by Darren Franich

If you're getting the sense this is a rather bleak comedy, it's important to underline just how breezy the tone of Back is. The ensemble faces their regular miseries with humor and hope, the latter even funnier because it seems so unjustified.

The Guardian by Ellen E Jones

It will take at least until the end of this six-episode run – and hopefully a few series more – to discover whether either Andrew or Stephen can really change. ... It is a testament to the masterful construction of this comedy-thriller that it remains possible to imagine they might.

Radio Times by David Craig

Not every joke hits the bullseye, but there can be no denying Back is a very sharply written show. It’s a witty sitcom first and foremost, but its intriguing overarching story also utilises elements from mystery thrillers and family dramas to great effect.

The Times by Carol Midgley

Mitchell and Webb being reunited is exactly the comfort food that television needs right now. Although Mitchell is ubiquitous on TV and radio, together they have a yin-and-yang alchemy that is as soothing as Sudocrem on a bottom rash, even if it is inevitable that one keeps comparing Back to Peep Show.

The Independent by Sean O'Grady

Any actors who can extract comic value from the phrase “urinal cakes”(Mitchell and Webb); and any team who can make us laugh as we confront deeply troubling mental health issues (what Stephen just calls being “mad” as “useful shorthand”) deserves recognition and the odd Bafta.

Los Angeles Times by Robert Lloyd

Mitchell and Webb, who have been a team more than two decades, are wonderful together, but they are just the heart of a crack, cracked ensemble, who embody a certain sort of eccentric British family familiar to readers of Austen, Waugh, Wodehouse and Gibbons.

IndieWire by Steve Greene

Even at six episodes, with a few harmless misadventures in between Andrew’s arrival and the season’s eventual fate, Back feels a little stretched thin. But again, as with so many other debut seasons of new shows these days, it arrives at an endpoint that signals a much better, more exciting show on the horizon.