On Monday ITV showed BAFTA Celebrates Downton Abbey, in which a massed gathering of cast and crew plus a few celebrity guests toasted Downton's five-year stampede to global acclaim. Its creator Julian Fellowes waddled onstage and told an anecdote about how he'd been accosted by a Downton fan while browsing in a Barnes & Noble bookshop in New York. "Just let Edith be happy!" she wailed at him.

Some things never change. Once more, we join DCI John Luther – though only for a two-part special – as he glues himself to the trail of a serial killer. And once again Luther is played by Idris Elba, a man who can freeze time or make villains throw down their weapons merely by gazing into the camera with an expression of quizzical world-weariness.

Though Alfred the Great was renowned for educational and social reforms as much as for whupping the Danes on the battlefield, I'd never pictured him the way David Dawson has been playing him in The Last Kingdom. Pallid and sickly-looking, and plagued by all-too-human frailties, this Alfred looked more like a weedy consumptive poet than the midfield dynamo of embattled Ninth Century England.

After the roaring success of Daredevil this year, Marvel brings us the next instalment in the TV rendering of their universe – or part of it at least. Jessica Jones, created by writer Brian Michael Bendis and artist Michael Gaydos in 2001, is a failed superhero and volatile PI who copes with her demons by drinking so heavily that at least one of her superpowers seems to reside in her liver. Super strength, near-flight and a fine line in withering sarcasm make up the rest.

They said there'd never be an audience for a period drama about an aristocratic Edwardian family. Six series later, we're bidding adieu to a national (and indeed global) institution, as Julian Fellowes's motley band of ridiculous, ahistorical and frequently exasperating characters potter off into the fading TV sunset. There's still the Christmas special, but – though we might not admit it – we'll miss them.

It's the age of the prequel, sequel and origin story, and the ingenious Charlie Higson has decided that now is the time to give Robert Louis Stevenson's divided-self myth a superhero-style makeover. Action-packed and a little bit shocking, this supercharged Jekyll & Hyde (****) has the makings of a major hit.

Stunningly reinvented in series four, Homeland sustained the momentum with this tense and menacing fifth season opener. Carrie Mathison (Claire Danes) has now quit the CIA for a new job in Berlin, where she's working as head of security for billionaire philanthropist Otto Düring (Sebastian Koch). The past, however, is not giving up without a fight.

Revenge dramas are such a guilty pleasure - there's a vicarious thrill in watching a baddie being taken down in a way that we might wish to, but never would, in real life. And boy, but did Gemma take down cheating husband Simon in the closing episode of Mike Bartlett's Doctor Foster. Senior GP Gemma and hip property developer Simon's perfect life, with their perfect house and their perfect son was, of course, anything but - and finally it all came crashing down.

This is the first of two new TV series this week to feature a female police officer investigating the discovery of long-buried skeletons (the other one is Thursday's Unforgotten on ITV). The two shows are different in tone, but still reminiscent of numerous noir-ish policiers of recent vintage. It makes you wonder whether commissioning editors are trying hard enough. We hear a lot of earnest talk about "diversity", but it doesn't seem to apply to themes and subject matter.

TV series about the clergy are usually farcical, self-deprecating or just plain wet, so it's a pleasant surprise to find one that's prepared to slug it out with issues of good and evil. Compared to Rev, a wistful tragi-comedy about managing the terminal decline of the C of E, Midwinter of the Spirit wants to mount up and ride into battle against the Ungodly.