Notorious

When Alicia Huberman's father is found guilty of being a Nazi spy after the war, she throws a party, which seems on the face of it a little insensitive, or possibly a clever diversion to keep the FBI out of her hair. She is, after all, the closest relative, who might be a security risk, which is why they send Agent Devlin (Cary Grant) to check things out.

Alicia (Ingrid Bergman) appears light-headed in conversation and light-footed on the dance floor, a fun girl with a direct connection to the good times. If she's putting it on, muses Devlin, she sure knows her onions. What he doesn't realise then, but will learn later, she's more than game; she's set and match when it comes to courage under fire.

Devlin makes her an offer she can hardly refuse if she wants to keep up the illusion that she hated her dad and didn't know anything about his nefarious goings on. He asks her to go to South America to help the agency uncover a cell of Nazis in Rio de Janeiro. Of course, she says yes. Sounds like a gas, flirting with rich Germans and having herself a ball, all expenses paid by Uncle Sam. What she doesn't reckon with is falling for that sap, Devlin.

The chemisty is perfect. Although Bergman dominates by sheer force of character, Grant's cool persona slips effortlessly into her pocket. There is a certain menace lurking in the shadows of a deliciously lightweight entertainment, but you are never quite sure what it is.

The Nazis, led by the suavely unGermanic Alex Sebastian (Claude Rains), with his possessive, dominating mother (Leopoldine Konstantin) - a dead ringer of Rebecca's Mrs Danvers - keeping a constant vigil, are up to something, possibly to do with uranium, and the secrecy is so tight Alicia has to marry the infatuated Alex, much to Devlin's disquiet, before she can get anywhere near the truth.

The excitement lies in Alicia's subtefuge, which doesn't fool mum, before Alex realises that he has been duped and lied to by his ravishing bride. Hitchcock plays a long game, allowing his stars to be gay (old meaning) and frivolous, charming the pants off the audience, aided by Ben Hecht's witty script, before slowly pulling the knots tighter around the neck of the plot.

It is a masterclass by the class master of suspense.