What do you do when you’re hired to direct a flawlessly scripted Ira Levin play that is one of the most produced thrillers in history and was the longest running thriller on Broadway?

Nothing. Except pick  a great cast, and keep the work simple, elegant, and pristine.

And that’s just what Katie Malinson did with “Deathtrap,” which opened Friday, January 18 at the Lancaster Opera House. With a theatre workhorse like “Deathtrap,” that has played on professional and community stages all over the world, any adaptations or tweaks would detract from the intricate script. Malinson says, “I just focused on letting the play work. It doesn’t need to be messed with. It was a matter of finding the right cast.”

Malinson’s cast – Paul Todaro as Sidney Brule, Lindsay Brandon Hunter as Myra Brule, Joe Isgar as Clifford Anderson,  Kathleen Rooney as Helga ten Dorp, and Steve Jakiel as Porter Milgrim – keeps her on her toes, she says. “They are veteran collaborators with great instincts and insights.”

Levin’s script (winner of the 1978 Edgar Allan Poe Award from the Mystery Writers of America, and a 1978 TONY Award nominee) is the real star of the show. A playwright, his wife, his student, and a mystical neighbor is an interesting dynamic, and their motivations are still fresh, even  41 years later. “The notion of doing anything for fame and fortune is still applicable,” Malinson says.

For Rooney, her role as Helga the neighbor, is well nuanced. “All the characters in the play are not as they seem. There’s humor in Helga, but also determination and ambition.”

This sets up an important element story, too. Malinson reminds us that “Deathtrap” is written as a comedy-thriller. “We have to keep the comedy and the friction alive. There’s a fine line there. I really like the dark humor in the script.”

In the end, who dunnit?  It’s a classic.

“Deathtrap” is onstage at Lancaster Opera House to January 18-27. Visit www.lancopera.org for details. Some performances are already sold out!