One day, Poirot receives a visit from a young woman, who first says that she thinks she may have committed a murder and then suddenly simply bursts out "You're too old!" and just as quickly leaves again. Poirot is intrigued (and hurt) and starts looking into the identity of the young woman and what this supposed murder might have been.
Though I remembered the villain's identity, I'd been looking forward to reading this quite a bit, because most of the rest of the plot had escaped me. And on the whole I must say that I was pleasantly surprised. This felt like a much stronger plot than several of the novels that surround it chronologically (The Clocks, At Bertram's Hotel, Hallowe'en Party) and at least on the same level as A Caribbean Mystery.
Admittedly, again the mystery hangs on a specific misdirection (or in this case, you might say you get two of the same kind), and you might very well see through it if you're well-read on your Christie tricks, but generally the plot hangs together very well, the developments follow naturally and the ending is quite powerful.
It helps that Poirot is front and centre of this story - Mme Oliver also has a bigger part to play than she's had in previous appearances - and that we get to follow along as he investigates, questions and ruminates. Indeed, one could say that we've rarely been able to follow Poirot's thoughts more closely than in this one. There's a whole section in this novel where the reader gets to see when Poirot simply sits and tries to figure out the puzzle in his head. If you contrast this with the last few Poirot novels, it's quite a startling change.
Yes, it's a bit long-winded at times, and the plot could have been tightened up in places, but I will rate this quite highly for such a late-career mystery. In fact, I'll give this a 68 out of 100.
Another literal translation of this title, though we put it in the definite form (= The Third Girl). As usual with these late career releases, there aren't too many editions of this novel. In fact, even though there was a third edition in the late 80s, it never got a paperback release.
The 60s cover is fine, I guess. Not my favourite drawing style, but I suppose it works. Not sure what the harlequin is doing there, though. Delfinserien's cover from 1974 is a bit strange, to be honest. More of an art piece than a correct depiction of anything in the novel. I wonder why there are two women on the cover...
Finally, there's the 1988 cover. As usual Leslie Quagraine manages to work a skull into the image, this time in the form of a palette. At least the painting connection fits the contents of the novel, and of the covers here, this is the one I like best.