Canberra Repertory Society's Witness for the Prosecution

Conventional wisdom has always been that Agatha Christie wrote whodunit melodramas, says Aarne Neeme. But he's now directing what he sees as quite a different Christie work.

"Witness for the Prosecution is different. It's much closer to a tragedy than a melodrama. It has more of an emotional effect than the traditional question, 'whodunit?'," he says.

Neeme is directing Witness for his 15th production with Canberra Repertory Society, following the success of his production of The Threepenny Opera earlier this year.

Witness, first performed in 1953, is a courtroom drama. Leonard Vole (played by Cole Hilder) is on trial at the Old Bailey for battering an old woman to death. He pleads not guilty, and says that his wife, Romaine (Emma Wood), can prove his alibi. Romaine testifies – but as the witness for the prosecution.

'Witness doesn't have the conventional detectives – Hercule Poirot or Miss Marple – ascertaining what's going to happen," Neeme says. "It's much more for the audience to discover what the secret is."

Like many of Christie's non-series works, Witness uses the mystery thriller genre to serious effect, raising questions about justice, guilt and innocence.

The play is based on an early short story, first published in the United States in 1925 and collected in Britain in The Hound of Death (1933). The story was, Christie thought, "a mere sketch of an accused person and an enigmatic witness… It had no court scene in it, no trial for murder." Certainly not enough to hold the stage for three hours.

She needed to heavily rework the story to bring it up to the standards of her work three decades later.

What interested her, Christie wrote in 1945, were "the preliminaries of crime. The interplay of character upon character, the deep smouldering resentments and dissatisfactions that do not always come to the surface but which may suddenly explode into violence."

From the late 1930s, the action is increasingly seen through the eyes of the people involved in the case, rather than the detectives trying to solve the mystery, and the solution relies on understanding human nature.

Christie's interest in people, ear for dialogue and sense of pacing and dramatic structure naturally led her to the theatre. Although she is the world's best-selling novelist, her detective stories translated into 103 different languages, and only outsold by Shakespeare and the Bible, the stage was her passion.

She wrote the world's longest running play, The Mousetrap, a classic snowbound country house mystery, with one set and a cast of eight which has clocked up more than 26,000 performances in London since it opened in 1952. As well as straightforward mystery plays – Black Coffee (1930), And Then There Were None (1943), Appointment with Death (1945) and The Hollow (1951) – she wrote a historical play about the heresiarch Akhnaton (1937), and reworked Death on the Nile as a J.B. Priestleyesque time play (as she would Five Little Pigs) and Towards Zero as a study of the events leading up to murder. Her early, unperformed plays discovered last year are Shavian high comedies that deal with eugenics and divorce.

After Witness, she would write mystery comedies (Spider's Web, 1954), suspense thrillers and studies of the dangers of idealism (The Unexpected Guest and Verdict, both 1958), and one-act experimental plays in the spirit of Terence Rattigan (Rule of Three, 1962; Fiddlers Five, 1971).

With this theatrical experience, Christie turned the "sketch" of a short story into a compelling, tense drama that twists and turns like an electric eel suffering from St Vitus's dance.

"Once you look at her play in detail, and at the cut and thrust of the dialogue," says Neeme, "everything is very carefully thought out."

Christie developed the characters of Leonard and Romaine,"the nervous, desperate young man in the dock, and the enigmatic woman who came into the witness box to give evidence not for her lover but for the Crown".

"Leonard and Romaine are fascinating in what they say and don't say," Neeme believes.

He compares Romaine, who left East Germany to follow her lover to England, to Euripides' Medea, "a woman wronged – a woman betrayed, who's given everything for love – and who exacts revenge".

Appearing on opposite sides of the law are two QCs, Sir Wilfred Robarts (Pat Gallagher) and Mr Myers (Peter Holland). "Their strategies are interesting," says Neeme. "The games they play with each other, the one-upmanship they try with each other, are well observed courtroom drama."

Christie went to great lengths to make that courtroom drama authentic; she read books of British trials, and consulted barristers about points of law and professional etiquette necessary for a play set in both a barrister's office and the courtroom at the Old Bailey. In Rep's production, Quentin Mitchell has designed a double stage set showing both sets.

She also changed the plot; the play ends in a stunning quadruple twist. The original producer, Peter Saunders, wasn't sure whether the ending would work, and wanted Christie to change it.

"I had to fight desperately for my chosen end to the play," Christie wrote. "Nobody liked it, nobody wanted it, everyone said it would spoil the whole thing."

Christie's belief in her ending was justified. Witness was a smash hit on both sides of the Atlantic when it opened at the Winter Theatre in London in October 1953, where it ran for 16 months, and in a double Tony-winning production on Broadway in December 1954. Billy Wilder's Academy Award-nominated film, starring Charles Laughton, Marlene Dietrich, Tyrone Power and Elsa Lanchester, followed in 1957.

Christie herself considered it one of her two best plays, with the unsuccessful Verdict. "I was as nearly satisfied with that play as I have been with any."

Canberra audiences should also be satisfied. As the posters of 50 years ago said: "You'll talk about it, but please don't tell the ending!"