Three out of Five stars
Running time: 90 mins

Engaging, sharply observed relationship drama, enlivened by strong performances from all four leads, though the fact that it constantly feels stagey and contrived is something of a distraction.

What's it all about?
Written and directed by Massy Tadjedin (writer of one of Knightley's best early movies, The Jacket), Last Night stars Keira Knightley and Sam Worthington as Joanna and Michael Reed, an affluent New York couple who are having trust issues. After meeting Michael's sexy colleague Laura (Eva Mendes) at a company party, Joanna challenges Michael to admit he's attracted to Laura, noting that he has never mentioned her before.

Joanna's timing is less than fortunate, however, because the next night, Michael heads off to Philadelphia for a weekend-long business trip with Laura and another colleague (Daniel Eric Gold) and with Joanna's words ringing in his ears, he quickly realises that Laura is attracted to him too. Meanwhile, Joanna is startled when she runs into Alex (Guillaume Canet), an old flame from Paris that she's never told Michael about.

The Good
All four performances are superb, even if Mendes gets short shrift in the character depth department compared to the other three; she does, however, make an excellent sexy temptress. Knightley, in particular, is terrific - her stick-thin physicality works well for her emotionally brittle character and she has strong chemistry with Canet. It's Worthington who is the real surprise here, though – at first you think he's being rather wooden and emotionally closed-off, but you gradually realise that that's a key part of Michael's character and that, actually, he's a little bit boring.

The plot may play out in predictable fashion (forcing you to consider exactly what constitutes cheating and so on), but the film's key strength is that you engage with the characters and find yourself asking what you'd do in their situations. By the same token, it's hard to imagine Last Night finding much success as a date movie, since the post-film couple conversations will almost certainly lead to either a) arguments or b) awkward silences.

The Bad
The main problem with the film is that it constantly feels both stagey and contrived, all of which eventually becomes rather distracting. Similarly, the ending feels too much like the conclusion of a short story, instead of addressing the consequences and delivering the anticipated emotional fireworks.

Worth seeing?
Staginess issues aside, this is a superbly acted, well written relationship drama that's both thought-provoking and emotionally engaging, though you might want to think twice before taking a significant other to see it.