Even before the opening credits the identity of this week’s killer isn’t in doubt; a well-dressed woman (played by Alicia Witt and later named as Dana Powell) sells some jewellery for cash, then shoots a homeless man. The motive clearly isn’t robbery, though, because Dana tucks an envelope filled with money – together with a quote about the relative value of rich and poor people, and a mathematical formula – into one of his pockets. So not a whodunnit, but a whydunnit. The homeless guy won’t be the last to be murdered, either, and in due course a connection between the victims will emerge: they are all related to people who died in a plane crash, for which the compensation to be paid has still to be sorted out. As ever with Elementary the plotting is ingenious, even if one or two of the leaps of logic had to be taken on trust.
And back at the brownstone Watson is in the process of moving in, and therefore out of her own apartment. Holmes treats the situation with unusual thoughtfulness and compassion, and compared to a few episodes ago – when Watson was behaving as if she couldn’t stand to be in the same room as Holmes – the show’s central relationship is back to being uneasy but intriguing. ‘When Your Number’s Up’ is a reasonably good episode. But it feels as if there’s something missing, and in the absence of any other evidence I’m going to say that the something is played by Ophelia Lovibond.