Colin Mochrie and Brad Sherwood are “Asking For Trouble,” their 10th show (with a gap for the COVID lockdown), March 29, State Theatre Center for the Arts, Easton.

It is not surprising that many attend the show every year since each performance is different.

Mochrie and Sherwood, who were on the British and American versions of the TV show, “Whose Line Is It Anyway?,” are probably the best-known touring improvisational comedians. They have been working together for 23 years.

Of the duo’s popularity in the Lehigh Valley, Mochrie quips, “They haven’t caught on yet.”

This year’s show will include a musical selection about Easton, even though, Mochrie says, “Only one of us can sing.”

The song will not be written ahead of time. The music will be selections from “80s karaoke tunes on shuffle,” so the duo does not know what the musical score will be.

In a phone interview from his home in Toronto, Canada, Mochrie says that he and Sherwood will appear at the State Theatre without props on an unadorned stage.

As is customary in improv shows, the two will first ask for audience suggestions for their games (the improv name for bits and sketches).

“We mix familiar games from ‘Whose Line?.’ Some are adapted from there. And there are some new games. That way it is fresh for everyone.

“We don’t do anything political. That way the audience is against you. Everyone always applauds when we say that at the beginning of the show. We are not like John Oliver or Bill Maher. It is just goofy fun.

“We do well when things are going badly in the world. People want to forget about everything,” says Mochrie, recalling that many told him their shows provided relief after 9/11.

Mochrie is not afraid to let the audience take he and Sherwood on tangents:

“It is not scripted. That’s what we do. We like different kinds of suggestions. It gets us out of our comfort zone.”

This year’s tour, “Asking for Trouble,” will typically include 150 shows. Mochrie and Sherwood have performed in Australia, New Zealand and India.

“Whose Line Is It Anyway?” began in 1988 as a British radio show. The same year, the British TV version began, which lasted until 1999. The American version premiered in 1998 and is still running, with a gap from 2007 to 2013. Many full episodes can be seen on YouTube.

“It’s aged fairly well, with references to some current events of the time,” says Mochrie.

“We get a lot of younger viewers to our shows, some that were not even born in the Drew Carey years.” Carey was the host from 1998 to 2007.

A few purists insist that “Whose Line” is not real improv because the format is limited for television.

Because of time constraints, Mochrie says, “It is somewhat ‘jokey,’ and it is hard to build a character in a scene. It is the vaudeville of improv. But it is still valid, and it is still hard to do.”

Mochrie has appeared on many Canadian and American scripted and improv TV shows. He prefers the latter:

“With improv, you are in charge of your own destiny. There is no producer, editor or director input. Whether we succeed or fail, it is on all of us.”

Mochrie believes that many things learned from improv can be applied positively to daily life:

“The teamwork makes you more empathetic towards people. You are always listening, accepting ideas without prejudice and building on them. You are living in the moment.”

“Colin Mochrie & Brad Sherwood: Asking For Trouble,” 7:30 p.m. March 29, State Theatre Center for the Arts, 453 Northampton St., Easton. Tickets: 610-252-3132, www.statetheatre.org