Those foggy days of 1880s London, all Hansom cabs, cobbled streets, urchins and women of easy virtue must have had among their tumult armies of TV crews all seeking out a dark and dank corner to shoot their pea-souper shows.
We know now that Sherlock is heading back to his usual period where he might venture down Ripper Street and, perhaps, be required to track down a menacing beast that is none other than Mr Hyde.
For that is where writer Charlie Higson begins his £17million take on the Robert Louis Stevenson character before hopping, budget unrestrained, to a touch of Ceylon on his way to art deco London with its turn-ups and clipped bon mots.
Jekyll & Hyde is ITV’s attempt to do a tea-time drama in the same vein as Dr Who, with enough of a fright – but not too much of one – to have the children torn away from their smartphones.
The convoluted family tree detour brings us ultimately to Tom Bateman’s mild-mannered Dr Jekyll who inherits his grandfather’s estate, and rather unfortunate anger management issues. Having spent his life with a kindly step-family in Ceylon, he returns to 1930s London to acquire his inheritance, both good and ill.
“You are cursed,” wails a crone. Yeah, we kinda know that.
In corrupting London and without his pills, Dr Jekyll begins to be plagued by the vein-popping, mascara-eyed, lasciviously grinning alter-ego and we await the phrase – “don’t me me angry, you wouldn’t like me when I’m angry” – as he goes all medieval on a music hall.
Indeed, in an audacious attempt at a land grab, Higson co-opts vast areas of popular culture including comic book heroes, X-Files, Men In Black, Batman, Superman and The League Of Extraordinary Gentleman all wrapped up in a swooping Sherlock coat.
Good ol’ RLS’s dark personality theme was an idea upon which an entire Marvel empire was built so it’s not surprising that dark duality theme is key.
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But that’s not all. No sir. When Richard E Grant’s military intelligence agents gun down Harbinger, a man-headed dog as part of a secret mission to keep the streets clear of monsters, we know that here’s a series that doesn’t lack for ambition.
Elsewhere, yet another secret organisation, Tenebrae, wants to recruit snarling bad-boy Mr Hyde in an episode so crammed it requires a spin-off.
We have yet to see if the series has, like Harbinger, more than enough legs to carry it through 10 episodes – but the signs are promising.