In his day job, Mitchell Reiter keeps a steady eye on the giant ships that come and go through the busy Los Angeles-Long Beach harbors in his role as a vessel control supervisor at the Marine Exchange of Southern California in San Pedro.

But over the next few weeks, Reiter will debut in a few new roles — as playwright, producer and lead actor — when his one-act play “Domino is Down” is featured as part of the seventh annual Hollywood Fringe Festival.

“I’ve dabbled in theater here and there,” said Reiter, a Colorado native who majored in English in college and studied professional screen writing at UCLA. “I wrote this play a couple years ago but wasn’t sure what to do with it. There’s not an easy way to get a play out in the L.A. theater community.”

“Domino is Down” tells the story of a conflicted dockworker who is torn between a job that provides a good income and doing something he loves more, but for less money.

“He’s trying to transition and is having issues doing that,” said Reiter, who is active in the Polar Bear swim club in San Pedro and knows many longshore workers. “He’s torn between two worlds.”

The five-actor ensemble features Reiter in the lead role and others who are seasoned performers, he said.

Director Jesse Feldberg, a Coast Guard veteran, is a filmmaker based in Long Beach.

The festival, something of a free-for-all, showcases some 300 productions at 30 venues around Hollywood, shining a light on innovative live theater in a town where film is king. The festival features self-produced shows and is based on the model of the Edinburgh Festival Fringe, founded in 1947 by theater groups in Scotland.

Reiter took on the acting role only when the lead actor they had originally hired didn’t work out.

“I’m not an actor, this is my first time doing it,” he said. “But I know I’ll be fine.”

The 55-minute play takes place in a bar inside a museum.

“We have a good set designer … it has more of a minimalist look, so visually it’s very interesting,” he said.

He’s mum when it comes to too many plot details, but noted that the play, which premiered before a small audience last weekend, does feature a surprise ending.

“There were audible gasps,” he said.

The play is being staged at the 50-seat Lounge Theatre, 6201 Santa Monica Blvd. Performances are at 4 p.m. Sunday, 2 p.m. June 17, 8 p.m. June 21, and 8 p.m. June 23. Tickets are $15.