Are we coming or going?

If the cast of South Coast Repertory’s production of “Noises Off” misses cues or stumbles through lines, it’s because it’s part of the script.

The farce, which the cast claims is as difficult to stage as it is funny to watch, hits the stage at South Coast on Friday.

“It’s a love letter to the theater,” said Bill Brochtrup, who plays Garry Lejeune, a stuttering actor whose speech impediment miraculously disappears when he’s on stage.

Written by English playwright Michael Frayn, “Noises Off” follows the third-rate cast of an off-color play within a play called “Nothing On.”

Each of the three acts of “Noises Off” includes the first act of “Nothing On” as the cast stumbles through a series of missed cues, poorly timed exits and entrances, and flubbed lines.

The relationships between the actors deteriorates over the course of the play.

While the cast of “Nothing On” deals with endless on-stage disasters and a behind-the-scenes love triangle, things rarely get as bad behind the curtains of a real play, Brochtrup said.

“It’s like if you took everything that could ever go wrong in the course of a play and magnified it — that’s what these actors go through,” he said.

The theatrical talents of the cast of “Nothing On” are dubious at best.

“I think my character thinks she’s a much better actress than she really is,” said Jennifer Lyon, who plays Brooke Ashton in the play, an inexperienced actress who doesn’t take stage direction and is oblivious to other performers on stage.

Unlike the cast of “Nothing On,” the cast of South Coast Repertory’s “Noises Off” is chock full of stars.

Actress Nancy Bell, who plays Belinda Blair in “Noises Off” has appeared in numerous productions at South Coast over the past decade. Her past television work includes “The Sitter” for Lifetime Television and guest appearances on “Huff,” “Medium” and “Numb3rs.” Most recently at South Coast, she appeared in last season’s production of “What They Have.”

Brochtrup is best known for playing John Irvin for seven seasons on the ABC drama “NYPD Blue.”

He later reprised the role in the CBS sitcom “Public Morals.”

He also can be seen in the upcoming film “He’s Just Not That Into You.”

Lyon appeared on Broadway with stars like Ethan Hawke and Billy Crudup in Tom Stoppard’s “Coast of Utopia.”

The play garnered 11 Tony Awards. Lyon also has been in a series of Aflac commercials.

With its fast-paced script and slapstick humor, “Noises Off” is one of the most difficult plays Bell has undertaken — she’s even had nightmares about the script.

“It’s like a slot machine up here ... I never know what’s going to come out: three oranges or two lemons and a banana,” one actress laments over remembering her lines during the course of the play.

It’s a sentiment Bell can relate to and she finds it hard to stifle a chuckle during the scene, she said.

“That’s kind of what it’s always like with this play, you never know if you’re coming or going,” she said.

IF YOU GO

WHAT: “Noises Off”

WHERE: South Coast Repertory

WHEN: Friday through March 8

COST: Ticket prices range from $20 to $64. Low-priced preview performances are available for Friday to Feb. 12.

INFO: Tickets be purchased at www.scr.org, by phone at (714) 708-5555 or by visiting the box office at 655 Town Center Drive in Costa Mesa.

BRIANNA BAILEY may be reached at (714) 966-4625 or at brianna.bailey@latimes.com.