Audience members wait with bated breath for the climax of Nick Bernardi’s story about sleeping with someone after knowing her for only an hour. When the punch line is delivered, the floor shakes from the  gales of laughter echoing through the theater.

Although the idea of playing “Never Have I Ever” is not a new one, the actors at Under the Gun Theater, 956 W. Newport Ave., put a spin on the classic high school game, which involves audience participation and improv scenes. Following a successful four months at its Wrigleyville location, the improv show has been extended through the end of September.

The game is played with prewritten cards containing embarrassing statements that are assigned to audience members at the box office. Cardholders visit the stage to read the statement, and if an actor has done what the card reads, he or she will explain the story behind the experience.

After the actors have explained their stories, they perform a series of improv scenes that are usually based on the personal anecdotes they have shared.

“You want to take bits and pieces from the stories that inspire you to create a scene,” said Erin Diehl, an actress in the show.

Although the actors shamelessly told their cringeworthy stories, Bernardi admitted that he sometimes shares his second-worst story to play it safe because the worst is too inappropriate to be told in front of people.

Kevin Mullaney, the theater’s artistic director, said actors have to edit themselves onstage when performing improv. Mullaney is usually the host, but he likes to perform when the cast is shorthanded, as he did on Aug. 28.

Mullaney said Angie McMahon, Under the Gun executive director, came up with the idea for the show. McMahon and Mullaney thought the game would make a good show because when performing “Never Have I Ever,” people confess a lot of personal information, which can be a good basis for comedy.

“It’s a fun excuse to tell a story that you might not otherwise tell,” Bernardi said.

“Never Have I Ever” encourages audience members to participate in the storytelling aspect of the game. Actress Sam Howard said it is great when the audience participates, and that they sometimes remain on the stage for a while, whereas other times participants get embarrassed and return to their seats quickly.

To keep things interesting, the actors do line skits using cards from other games between rounds of “Never Have I Ever.” One segment from the Aug. 28 show was called “Sex with me is like…” and was played with cards from “Apples to Apples.” The host would read a card to complete the phrase, and the actors would take turns making one-line statements explaining why that card represents their sex life.

“Never Have I Ever” began its run at the theater in May, and the audience size has not fallen off since. Mullaney said figuring out how long to run a show is tough but after a while it becomes easier to sense the “hook” a certain show has.

The decision to extend the show through September was made based on its popularity.

“We have generated an audience that keeps coming back,” Mullaney said.

Upcoming shows at the Under the Gun Theater can be found on the theater’s website as well as flexible pricing for tickets to most shows. Buyers can change the price to whatever they feel like paying. The options range from $3 off to free depending on the show.