London theater celebrity checks out Walnut's staging of "The Mousetrap"

Theater people want every performance to be memorable for each new audience. But the pressure really mounts when a theater celebrity is in the audience, as was the case Sunday when Sir Stephen Waley-Cohen flew in from London to see the Walnut Street Theatre's production of The Mousetrap.

Familiar doesn't come close to describing Waley-Cohen's relationship with the venerable Agatha Christie murder mystery, which has been performed in London since 1952 - the longest continuous run of a play in history, according to Guinness World Records. Waley-Cohen has been its producer there since 1994.

"Are you having fun?" he asked the eight cast members gathered on stage to meet him privately after Sunday night's performance. They shook his hand and accepted his praise for a job well done.

Mousetrap Productions decided to mark the play's 60th year by licensing 60 productions worldwide, and the Walnut, marking its own 203d season, is among the few and the proud. Amy Rodgers, of the Walnut's public relations office, said the cast had been kept in the dark about Waley-Cohen's presence until the last possible minute.

"What kind of reception have you been getting?" Waley-Cohen asked. The actors murmured contentedly, and Bernard Havard, the theater's producing artistic director, said the Jan. 25-March 4 run is poised to break the Walnut record for single-ticket sales.

"We budgeted $230,000," he said, "and now we're near $350,000."

Set in England during the winter of 1952, The Mousetrap concerns a group of strangers trapped at a manor house-turned-inn during a snowstorm. One of them is a murderer, and each is suspect.

Is it one of the newlyweds, or the spinster with the curious background? The architect, the retired army major, or the dapper old man who claims his car overturned in a snowdrift?

What about Professor Plum with the candlestick in the conservatory? Don't even go there.

Dame Christie (1890-1976) said she was inspired to write The Mousetrap by the real-life case of Dennis O'Neill, a boy who died while in the foster care of a Shropshire farmer and his wife in 1945. The play has not been updated over the years - unlike the classic board game Clue, which was reissued in 2008 to entertain the possibility that the murderer might be Cassandra Scarlet (no longer a Miss) with the barbell in the spa.