Bob Fischbach / Omaha World Herald

Snuggled in the Hamptons of east Long Island, Kevin and his husband, Ted, have what looks like a cushy, harmonious life in Sag Harbor, New York.

But then in “Harbor,” playwright Chad Beguelin’s biting adult comedy that SNAP Productions opens tonight, Kevin’s badly behaved sister and her teen daughter show up.

“Basically, she moves in and causes all this turmoil,” director Michal Simpson said, “and that leads them to look at their 10-year relationship and what they want out of it, and at their own lives.”

Beguelin is a four-time Tony nominee who wrote the book for “Aladdin” for Disney as well as some lyrics for the musical. He also wrote lyrics and co-wrote the book for the musical “The Wedding Singer” and lyrics for “Elf the Musical.”

Simpson found the script for “Harbor” more than a year ago, when the off-Broadway hit was less than a year old, and decided it was “right up our alley.” SNAP stages plays that promote tolerance for gay people. In “Harbor,” he saw smart comedy that dealt not only with sexuality but adoption, family relationships and more.

“It has some moving moments, as well,” he said. His challenge as director was to coax honesty and realism from his cast about the characters’ relationships amid the one-line zingers, Simpson said.

The subtext is more interesting, he said, because 14-year-old Ryleigh Welsh often plays the character who is acting most adult-like. Simpson said Welsh, a freshman at Central High School, “is giving these grownups a run for their money.”

While Welsh is new to SNAP, Simpson has worked with Noah Diaz and Joshua Mullady, as Kevin and Ted, and Kaitlyn McClincy, as the sister, in past productions. He said he pushed the three to stretch their character-building skills.

On March 14, SNAP will host a talkback after the show with cast members, plus Drew Heckman of the Human Rights Campaign, Tyler Richard of the American Civil Liberties Union and others.