The children got Malory Towers. Now it’s the grownups’ turn. Just as the BBC’s Enid Blyton adaptation was brought forward to keep the juvenile masses entertained when the schools shut early, so the corporation has pulled season three of Killing Eve (BBC Three) from its intended summer slot and placed it before us. Hopefully it can provide some welcome relief to the unique and uniquely wearing combination of panic and boredom that characterises life in lockdown.

It will, I hope, not count as a spoiler if I say that Eve (Sandra Oh) is alive. She survived Villanelle’s (Jodie Comer) bullet in Rome. Somehow the supreme assassin did not linger to see if she had done her job properly, or put an extra couple of bullets through her victim’s head to make sure, meaning Eve is now back in England, working in the kitchen of a Korean restaurant and occasionally visiting her husband, Niko, who is in rehab.

Villanelle is marrying a rich Spanish woman and inappropriately musing, as secret pseudo-lover killers will, about her ex during the wedding speech (“I’m so much happier now she’s dead”) before launching herself at an unexpected guest – her former trainer and handler Dasha (Harriet Walter). After a knockdown, drag-out fight between erstwhile mentor and mentee, Villanelle is restored to the assassin fold via the promise of being made a “keeper” (management-level stuff, which promises to work out as well for the world’s most dedicated and impatient loner as you might think) and sent out on another job to check her murderous skill set hasn’t rusted since it was last exercised.

Meanwhile, Carolyn (Fiona Shaw, whose character is given more emotional meat to chew on by the end of the first episode than she has had for the entire run so far) is being punished for her various unauthorised actions over the past series. A “Whitehall warrior”, Paul Bradville, has been given her office and most of her authority. He is played to perfection by Steve Pemberton, who specialises in people who make your hackles rise and your teeth itch as soon as they open their mouths.

Carolyn’s son, Kenny, is still living with her but has left MI6, disgusted and infuriated by the events of last season and his mother’s hand in them, and is working as a journalist for a website called Bitter Pill. While you might be able to take the boy out of the intelligence services, the boy remains curious, and is continuing to investigate – to his ultimate detriment – the activities of The Twelve, who do not seem as chastened as you might hope. “Now I’m back,” he says, when Carolyn recalls his “defection” from his original post at MI6 for the Foreign Office. “With bells on!” “So we can hear you coming,” says Carolyn, because Carolyn gonna Carolyn til the end of time, and I, for one, will slavishly follow her until the scroll rolls up.

And it’s all fine. It’s fun, with gasp-out-loud moments, and the series remains visually more appealing than almost anything else currently on screen. Comer is compelling, and with Eve in the aftermath of trauma, Oh gets the chance to add some depth to the detective. But there are fewer glorious flourishes so far, aesthetically, verbally or narratively. Even Villanelle’s first job, though lauded as a triumphant improvement on a legendary hit by Dasha back in her own heyday, feels underpowered (though in fairness this may partly be in order to lull us into a false sense of complacency before the closing scenes back in London).

Like the second series, it is still a high-quality, high-wire act, but it cannot quite match the verve and wit of Phoebe Waller-Bridge’s original episodes. A further burden now – and one shouldered by any subsequent series after one based on a cat-and-mouse premise – is that the artifice is showing. More and more elaborate ways must now be found to keep Eve and Villanelle apart, and other plotlines added to keep the central relationship from fulfilment and – given this one’s essentially fatal nature – ending. So Killing Eve is becoming less dark, less knotty and more traditionally procedural, which feels like a sad loss even if what remains is still head and shoulders above the competition.

Only a supreme cynic would wonder if its transfer from the summer slot to now, with a wholly captive audience, wasn’t just a very welcome supplement to our viewing diets but also a useful boon for the programme itself. But here we are. Even if Killing Eve isn’t quite killing it as she used to, it’s good to have her back.

• This article was amended on 14 April 2020 as the restaurant Eve worked in was Korean, not Chinese.