Second only to her record-breaking success The Mousetrap (still running in London more than 50 years after it premiered), Witness for the Prosecution is by far Christie’s most successful work for the stage. It premiered in 1953, with David Horne and Patricia Jessel lauded for their work as a defense attorney and the emotionally detached woman who becomes the crux of his current murder case, respectively. In 1957 – when Christie’s fame was at its peak – Witness was adapted into a successful film, which remains engaging to this day.

Tyrone Power as Leonard Vole

I’m not familiar with the play, so I’m taking things entirely on the basis of this film. When a rich but lonely older woman (Norma Varden) is murdered, Leonard Vole (Tyrone Power) is arrested: he had become increasingly close to the lady, to the point where she changed her will to include him as the beneficiary, and all the circumstantial evidence points toward him. The only element of doubt lurks in Vole’s supposed alibi, but it’s one that likely won’t stand up in court: the word of his German wife Christine (Marlene Dietrich). Desperate but determined, Vole manages to acquire the services of lauded QC Sir Wilfred Robarts (Charles Laughton), and from here we speed through the pre-trial preparations, as we head toward an intense court battle.

Witness for the Prosecution is immaculately contrived, presenting us with a case that doesn’t hinge on suspects – it was either Vole or it wasn’t, that’s all that matters – but instead on the evidence and the characters. Laughton fairly steals the show as Sir Wilfred, who is supposed to be on an extended holiday due to his ill-health, but (naturally enough) refuses to listen to medical advice so that he can tackle this case. Laughton is effortlessly canny, with a sparkle in his eye that picks up on every little twist and turn. Like Daniel Benzali in Murder One four decades later, Laughton can switch in a heartbeat from comedy to tragedy, as he gradually realises the murky levels of the case he’s dealing with.

Equally delightful is Laughton’s real-life wife, Elsa Lanchester, who plays his nurse Miss Plimsoll (a character invented for the film). The first third (pre-trial section) of the film showcases Laughton and Lanchester’s dynamic chemistry, with Plimsoll becoming increasingly demented as she attempts to hold the reins on the indomitable Sir Wilfred. Although she takes a backseat once the trial begins – watching from the gallery, interrupting to force the QC to take his pills, and developing a bond with the woman sitting next to her – Lanchester shows why she was one of the most respected actresses of her generation.

Elsa Lanchester as Miss Plimsoll and Charles Laughton as Sir Wilfred in a publicity shot

As the trial begins, director Billy Wilder manages to squeeze every inch of life out of the courtroom. I’m a fan of courtroom drama, but I understand why it doesn’t appeal to some: characters standing in the same positions, debating back and forth, doesn’t hold the requisite drama for some. Me? I’ve always enjoyed it, but Wilder manages to make the interrogations seem as lively as an action film. The courtroom overflows with life, from the bickering between Sir Wilfred’s team and the prosecutor (a very solid Torin Thatcher) to the friendship Miss Plimsoll sparks with the blonde (Ruta Lee) sitting in the gallery, as they bond over dislike of one witness, and concern for others. When the deceased’s opinionated housemaid (Una O’Connor, reprising her role from the play) takes the stand, and unwittingly becomes a joke amongst the spectators, it feels utterly natural. No “rhubarb”ing from the extras here.

As the prisoner, Tyrone Power tends to go unnoticed in reviews – playing second fiddle, as he does, to the Lanchester/Laughton pairing, and the star name of Dietrich. But in this – his last film before a tragic heart attack on the set of his next – Power, still handsome even in his post-matinee idol days, is strongly cast. He’s got a tough role, since we don’t know if Vole is guilty or innocent, but he manages to retain the character’s central ambiguity while earnestly playing both his despair and the moments when he appears to be hiding things.

Marlene Dietrich as Christine Vole

Finally, there’s Marlene Dietrich in a strange performance as the prisoner’s wife. Christine proves a spanner in the works, when she unexpectedly rescinds her alibi and becomes a witness for the prosecution (hey! that’s the title!). I’m not sure at all how I feel about Dietrich in this film. It’s very hard to analyse her performance without spoiling the film, but we know from the start that she’s aware of more than she lets on. There are certainly layers to Dietrich’s performance, and she’s very good in the final scenes, but her performance is far more dated than the others. The ’50s was the beginning of the end for the “old-school” style of acting, and Dietrich was a little less on the naturalistic side as it was. Still, she’s always interesting to watch (even if the flashback to her meeting Vole feels like an excuse to show some Dietrich legs… and really goes on too long), and proves a worthy opponent to Sir Wilfred. The interplay between the wife and the QC is the true heart of the film, with Sir Wilfred ever suspicious, and determined to get to the heart of justice, no matter what the cost, while Christine is clearly playing her own angle.

At the end of the day, Witness for the Prosecution is a sparkling, clever movie. Laughton, Lanchester and Wilder were all deservedly nominated for Academy Awards (Dietrich wasn’t, and some claim this was because United Artists didn’t want to draw attention to certain elements of her performance which might ruin surprises for the viewer.) Christie’s plotting leaves no stone unturned, with every clue cleverly placed throughout the story – some of them cleverly disguised to the point where you don’t realise they’re even clues. Given how influential Christie’s methods were, you may not be as surprised as contemporary audiences. I wasn’t, since shows like The Practice have long made such twists standard fare. But even then, I guarantee at least one element of the solution will surprise you. And while the final lines might be a little bit ‘Rule Britannia’ for my liking, I suppose it’s the only way to end a film of that era.

All in all: exquisitely cast, beautifully directed, cleverly plotted. Definitely a high point of Dame Agatha’s career, no doubt about it.

Edited to add: since posting this review, I tracked down the 1982 film, which boasts a cast including Deborah Kerr, Wendy Hiller, Beau Bridges, Diana Rigg and Ralph Richardson. You can find my review here.)