For many people outside the London sphere, the closest they'll have got to The Mousetrap is while playing Trivial Pursuit (and yes, it remains the longest-running West End show, trivia fans).

In this, its diamond anniversary year, Agatha Christie's stellar stage whodunnit is being brought to the wider UK masses, from Aberdeen to Truro, until the end of June next year.

The Theatre Royal is only its second touring venue, but the production already seems very practised and comfortable, and in no way stale. The stunning wood-panelled set, the main gathering area of Monkswell Manor, alerts us to the period of the piece, and Christie's dialogue, although it has dated in nuance, speaks enough of the human psyche to keep a more challenging and cynically modern crowd at cheer.

Downton Abbey's Thomas Howes plays Detective Sergeant Trotter, the young man who intends to get to the bottom of the first of a potential three murders that relate to the children's song Three Blind Mice. Throw in a newlywed couple who have just opened the manor as a guest house, plus five very unusual house guests, and the stage is set for a typical denouement - or is it?

Collusion with the audience is part of the appeal of The Mousetrap: being asked to "keep the secret" makes everyone part of the sleuthing crew who are in on the plot, now privy to the twist. To talk more of characters would perhaps reveal too much, so suffice to say that Ian Watt-Smith's direction of his younger cast members, particularly Steven France and Clare Wilkie, was both assured and compelling. And theatre trivia fans note: the mantelpiece clock has featured since opening night in 1952.

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