What’s the good of having a refrigerator without someone to play with the magnets?  

Here in New York, the weather is unseasonably warm, and no joke. Thinking it a bad idea to overdo the spring-feverish liberation from heavy clothes, I wore what I’ve been wearing lately, minus the sweater and the scarf. A mistake; I got quite hot, running an errand up to Carnegie Hill. I was tempted to take a taxi home, but I couldn’t decide what to do for lunch. The Shake Shack, as you can imagine, was crowded, with a line threading along the window from the door — and then down the stairs, of course; it would have taken forever to do lunch. And I’d left my copy of the London Review of Books at the movies, dammit.

That’s not like me, but I was so bowled over by Unknown that it was all I could do to collect my jacket and my shoulder bag. I’m not going to appraise the plausibility of the screenplay; the best thing to be said about it was that it is never implausible. That’s because what happens to Dr Martin Harris seems so implausible to him, and Liam Neeson knows how to make Martin’s befuddlement so agonizing to us, that we’re not inclined to evaluate the likelihood of anything. The acting is superb all round — even January Jones is riveting — and Berlin provides a sleek and cosmopolitan setting. (The famous Adlon Hotel lends its services, presumably suffering no damage that CGI can’t undo.) The action is breathless but never incoherent.

Unknown depends upon the audience’s misreading of the opening scene, in which Martin and his wife, Liz (Ms Jones) fly into Berlin, where Martin is to make a presentation at a science conference. If you’ve seen the trailer for the film, then you know that Elizabeth is going not only to deny knowing Martin at the conference but also to claim that another man (Aidan Quinn) is her husband Martin. It’s quite the nightmare, but only if you make the assumptions about Martin and Elizabeth that the film wants you to make.  In this way it is different from the Bourne movies, where Jason Bourne, like a patient in analysis, seeks to retrieve memories of a past that trauma has erased. Martin Harris’s trajectory goes in the opposite direction. He wakes from a coma, four days after an accident, alarmed to discover that only he knows who he is.

Diane Kruger, who played the vampish counterspy in Inglourious Basterds, is fierce rather than glamorous this time; she playsGina, an illegal immigrant from Bosnia whose palette of hardscrabble jobs run from driving a taxi to waiting in cheap restaurants. Although Martin promises to make it up to her for bringing so much trouble into her life (and, in the end, delivers on his promise), Gina comes across as Martin’s scrappy protector, almost a patron saint. She’s physically fearless (at least behind the wheel of a car), and she has enough common sense to make up for Martin’s lack of it. Among the supporting actors, Bruno Ganz stands out as a ruminative former Stasi detective who meets his own end with courage; he seems to have seen everything and thought about it all at least twice. Other German actors who make Unknown a first-rate entertainment include Sebastian Koch, as a brilliant genetic biologist, Rainer Bock, as the Adlon’s manager; and Karl Markovics and Eva Löbau as the doctor and nurse who care for Martin during his coma and afterward. All I can about Frank Langella’s contribution is that you know that he’s playing a very bad man just by the way that he sounds like a really nice one.

I always sit in the back of movie theatres because I don’t want to risk blocking someone else’s view, but today I had another reason to be glad that there were only one or two people sitting in rows further from the screen: it hit me at the end that I must have put on quite a show myself, what with all my flinching and ducking and wincing and eye-hiding. If possible, Unknown is even more viscerally challenging than Mr Neeson’s last adventure, Taken. You can see why I forgot my LRB.

The picture of Will that I wish I’d been able to take would have shown him darting about the apartment with his left hand in his father’s and his right hand clutching a yardstick with the authority of a rudimentary Wotan (or Siegfried, maybe). At one point, he stood still enough for his mother to determine that he is 31 inches tall. He is thirteen and a half months old.  And quite pleased with himself: when he replaced a refrigerator magnet after having just pried it loose, he applauded himself in his soundless way — he doesn’t bring his hand all the way together. In my own soundless way, I applaud his parents.