It is a rare thing, in these high-quality, high-stakes, immaculately professionalised TV times, to see someone on screen who can only 80% act. But now, like only semi-convincing buses, two such performers have come along at once in Batwoman (E4), the CW’s new entry into the Arrowverse. One of them is Dougray Scott, whom you may 80% remember from his villainous roles/substantial cameos in about 80% of things since the mid-90s. He plays Jacob Kane, the brother of Martha Wayne and the head of the Crows, the private-security-firm-cum-army that has taken over the job of protecting Gotham City since Batman disappeared three years before we arrive in the story.

More problematically, the other 80-per-center is Ruby Rose, who plays Jacob’s daughter Kate Kane. By the end of episode one, she has broken into cousin Bruce’s bat cave and taken on his mantle. Her 80% covers all the scenes that do not require her to be superheroic. What made her so good in her breakthrough part, as Stella in Orange Is the New Black – her flair for comedy, the perpetual ironic glint in her eye and her ability to turn seductive at a moment’s notice – is great here for the connective tissue (the back story with the girlfriend she lost when the police training academy expelled her for being gay, the banter with comic book baddies and so on). What she can’t muster is the full-hearted saviour-of-Gotham approach needed in other scenes, or the emotional gush that Kate’s daddy issues and survivor’s guilt (from the childhood car crash that killed her mother and her twin sister) periodically require. And that is before she is further hampered by the addition of Kate’s famous red hair, via a wig so preposterous it should come with a warning: fatally injurious to the suspension of disbelief.

Everyone involved, of course, might fare better if they had a decent script, proper lighting, well-choreographed fight scenes and sets that didn’t look as if they had been nailed together from whatever was left after Michael Keaton left the building in 1989. But you know what? Sometimes good enough is good enough. Sometimes a dead twin sister whose body was never found and a mad lady villain in an equally preposterous blond wig who knows the kind of details about a titular heroine’s life that only her missing twin sister could know is all the twist you can handle. Sometimes a gender flip is enough sophistication and sufficient justification for another foray into this, that or the other verse. If Batwoman were Watchmen quality, no one would have the mental bandwidth at the moment to deal with it.