Last night's episode of Sherlock on BBC1 – spoiler alert – was the third piece of prestige TV I've watched in as many months to conclude with the self-sacrificial death of the superpowered lone female member of a gang of outsider heroes. (The other two – spoiler alert – were Showtime's Penny Dreadful and Stranger Things on Netflix.) In every case, the self-slaughtering heroine gives her life not only to save one or more of her (male) comrades but also to atone for her sins or crimes of the past, and in rejection of the 'normal' life that she wishes she could have with one or other of the nerds she's dying for, but realises she can't because of her superpowers and/or the crimes she committed, even if she can't really be blamed for those crimes, because the ultimate fault rests with the evil forces that wanted to exploit her superpowers.

To the extent that they've thought about it at all – none of them's Euripides – I imagine that the creators of these shows (Mark Gatiss and Steven Moffat, Matt and Ross Duffer, John Logan) consider this a feminist move; at any rate it makes a change from one or more male heroes rescuing a damsel in distress. But it's lagging behind season five of Buffy the Vampire Slayer (2001), in which the heroine sacrificed herself to prevent her sister sacrificing herself to save the world. And it raises a few questions, such as: why are so many shows using this particular plot twist? Why are the male characters allowed to feel entitled to their normal lives, despite their superpowers and past crimes? Why does remorse have to come bound up with a desire for a 'normal' life? And why aren't there more women or girls in the gang?