As previously announced, the critically acclaimed production will play its final performance at the Cort Theatre Jan. 4, 2009. That date will also mark the final performance of Sam Robards in the role of Hannay.

When the show resumes performances at the Helen Hayes Theatre on Jan. 21, 2009, Sean Mahon will star in the quick-change comedy.

The cast also currently features Arnie Burton (Man #2), Francesca Faridany (Annabella Schmidt/Pamela/Margaret) and Jeffrey Kuhn (Man #1) with Rob Breckenridge, Claire Brownell and Cameron Folmar.

Sean Mahon made his Broadway debut in Conor McPherson's The Seafarer. His other theatrical credits include Savage in Limbo, Translations, Ourselves Alone, The Visit, Stones in his Pockets, Yankee Trader, Confessions of a Catholic Child, One for the Road, Drama at Inis and Big Maggie. His screen credits include: "Fringe," "As the World Turns," "Angel," "The Agency," "Everwood," "ER," "Line of Fire," "Sci-fi MOW," "Hulk" and "Mr. and Mrs. Smith." He is a founding member of The Virtual Theater Project.

The 39 Steps, according to press notes, "features a cast of four actors who, against all odds, breathlessly and hilariously attempt to reenact all of the characters, locations and famous scenes in Hitchcock's 1935 film thriller with just a few props and a lot of theatrical ingenuity and split second quick changes."

The 39 Steps is adapted by Patrick Barlow and directed by Maria Aitken. The production is based on an original concept by Simon Corble and Nobby Dimon and on the book by John Buchan.

Tickets for all performances are available by calling (212) 239-6200 or by visiting www.telecharge.com. The Helen Hayes Theatre box office will open Jan. 5, 2009.