“Chia Pets!”

The voice rang out above dozens of others as the near-sellout crowd at Huge Improv Theater scrambled to suggest something nostalgic.

Then members of an improv comedy team stepped up to relate anecdotes and associations the phrase brought to mind — like how the shoulder-pad fashion trend of the 1980s made every woman look like a linebacker.

Ten minutes later, the team and the audience were in the thick of three off-kilter narratives, following a quintet of musically inclined fur trappers; a father intent on watching bizarre VHS tapes with his son; and a quest for the secret of Rob Lowe’s eternal youth. By the end of a half-hour, all of those seemingly unrelated stories managed to dovetail into something resembling a satisfying conclusion.

Welcome to the Harold. Or at least, one interpretation of the Harold. It’s all part of Huge’s “Harold Turns 50” celebration of what’s arguably the most important cornerstone of long-form improv.

So what exactly is a Harold? Basically, it’s a set of guidelines that help an improv team develop a scene. “The simplest explanation is just three story lines, each visited three times,” said Huge co-founder Butch Roy.

Harold Turns 50 What: The 50th anniversary of the improv form. When: 8 p.m. Saturdays through Oct. 28. Where: Huge Improv Theater, 3037 Lyndale Av. S., Mpls. Tickets: $12. 612-412-4843, hugetheater.com.

You can pick out the familiar beats of the Harold in just about every TV sitcom.

“A group of performers will take an audience suggestion and build on that idea in ways that are unpredictable even to the performers,” said Molly Chase, director of House of Whimsy, one of three teams that are performing at Huge every Saturday through the end of October. “There will likely be moments of poignancy and humor, and the whole room — audience and improvisers — are in it together.

“It’s immediate, it has never happened before, and will never happen again.”

Origin story

The first Harold was performed in 1967 by the Committee, a San Francisco-based comedy group known for experimenting with narrative structures that employed improv games and exercises.

When the group decided that it needed a name for its creation, one member reportedly cracked that “Harold” would be nice. The handle stuck, to the slight chagrin of generations of performers who have had to explain its origin.

Committee member Del Close dedicated much of his career to honing and teaching the Harold. In the 1994 book “Truth in Comedy,” generally regarded as the improviser’s bible, he and co-authors Charna Halpern and Kim “Howard” Johnson explain that “the Harold is like the space shuttle, incorporating all of the developments and discoveries that have gone before it into one new, superior design.”

Close’s efforts as an instructor and co-founder of Chicago’s iO Theater became the foundation for much of American comedy as we know it.

No local venue feels that influence more acutely than Huge Theater. With “Harold Turns 50,” Minnesota’s most visible improv venue is paying homage to its roots and giving some of the Twin Cities’ top improvisers a chance to get back to the basics.

“There are a lot of improv structures, but there’s something magic about the Harold, the way you start with an opening and it brings out a truth,” said Drew Kersten, director of the Kempt team.

Kempt assistant director John Gebretatose agreed that it’s all about capturing those truths. “It’s people playing with confidence … making comment on real-life things. Like women’s shoulder pads in the ’80s and how they had to look like football players just to get through life. For me, that’s what makes it successful: a through-line or a narrative commenting on society.”

One of the reasons improv remains a hard sell for some audiences is that it’s the ultimate “had to be there” entertainment. It’s difficult to explain how the shoulder pad observation might snowball into a scene about Jennifer Aniston devouring the life force of her young fans, but for those watching the performers feed off one another’s energy and make connections, the evolution is electrifying.

Those hazy connections are very much by design, Kersten said. “If the opening is about Diet Coke, you don’t want to see three scenes about Diet Coke. You want them spread out as far as possible, so when they start to come back together it brings a bit more of that magic.”

The laughs in a Harold show seldom come from a standard setup/punchline delivery. In fact, one of the first rules laid out in “Truth in Comedy” is “Don’t go for the jokes.” Instead, the comedy in a long-form show comes largely from watching relatable situations spiral into unexpected directions.

“The least successful Harolds are when we let our ‘I know where this needs to go’ take over and steer things instead of discovering all the way through,” Roy said. “Because if we know where it needs to go, so does the audience.”

Grounded weirdness

The form’s flexibility is obvious watching the three teams of five performers in the “Harold Turns 50” showcase.

On opening night, the House of Whimsy team produced a trio of focused, slice-of-life vignettes about crumbling relationships, disillusioned carnival workers and spiteful chess players. While the scenes frequently veered into weirdness, they remained grounded in a way that drew laughs of recognition from the crowd.

The Speficicity team, on the other hand, dove deeper into surreality right off the bat with a scene about two buddies literally riding each other’s good vibes like a surfboard. That story line soon intertwined with two bird-watchers who misplaced a baby, and a home brewer crafting a hugely popular beer that smelled of cat urine, all of it building into a crescendo of absurdity that had the audience roaring for very different reasons.

As much reverence as the local improv community has for the Harold, the form represents something different in the Twin Cities than it does in improv hotbeds such as New York, Chicago and Los Angeles, where making it onto a high-profile Harold team can be a major career steppingstone. Many performers move to those cities for that reason.

“In Minnesota it’s a strong part of the tradition, but at Huge Theater, Harold is only one of the forms that gets done,” Kersten said.

While Close did some work with Minnesota comedy godfather Dudley Riggs and his Brave New Workshop, Huge encourages experimentation and focuses more on building strong teams of performers, regardless of form.

“Team first, format second: That’s what differentiates us from the coasts,” Gebretatose said. “We’re better anyway,” he added with a laugh.

Ira Brooker is a St. Paul-based freelance writer and editor.