The secrecy shrouding the highest echelons of the Roman Catholic Church continues to fascinate both the religious and non-religious worldwide, making the highly guarded institution a natural setting for The Last Confession.

Fresh off sold-out engagements in the U.K., Roger Crane's acclaimed stage thriller kicks off its world tour with a Toronto run beginning Saturday at the Royal Alexandra Theatre.

Revolving around a crusading cardinal investigating the sudden and mysterious death of Pope John Paul I, who died just 33 days into his post, The Last Confession stars David Suchet, the Royal Shakespeare Company actor perhaps best known for playing Agatha Christie's iconic mustachioed sleuth Hercule Poirot on television, and fellow British performer Richard O'Callaghan.

Though John Paul's death in 1978 was officially attributed to a heart attack, he was buried without an autopsy, said Suchet. Because of the surprising occurrence and mysterious circumstances, unofficial conspiracy theories floated widely.

"Was he poisoned? Was he this? Was he that? Did people hate him because he was going to be so liberal and look at contraception and all the rest of it?" Suchet noted to CBC News.

From Dan Brown's bestselling page-turners to The Godfather: Part III, the entertainment world has long told Vatican-set tales of power and intrigue. Now, with Pope Francis newly challenging longstanding church traditions, The Last Confession and similar stories are once again timely and relevant.

In the attached video, Zulekha Nathoo looks at The Last Confession and the allure of Christian thrillers. In the attached audio, Suchet talks to Carol Off on As It Happens.

The Last Confession runs April 19 to June 1 in Toronto before touring to the U.S. and Australia.