Chris and Dave Walsh perform as The Ramada Boys in a video clip. The Walsh brothers return to Cambridge this week for a Sunday show in Harvard Square.

The Walsh brothers, whose Great & Secret Show became a years-long highlight of the Cambridge comedy scene, return Wednesday to the East Coast for their annual holiday visit.

According to David Walsh, their only scheduled time on stage is Sunday as hosts of the Comedy Studio’s Christmas Party. The show should start at 8 p.m. and cost $8, like typical shows at the Harvard Square comedy mainstay, and include Tony V, Kelly MacFarland, Tim McIntire, Sean Sullivan, Renata Tutko, Zach Sherwin (soon to join the Walsh brothers in Los Angeles) and Ken Reid.

Soon after arriving in Los Angeles, the brothers started a Great & Secret Show in the Improv Lab of the famed Hollywood Improv, reviving as well their notoriously loose and enjoyable storytelling and casual approach toward free and free-flowing alcohol. The Improv eventually caught on to their trick — the alcohol-free punch was spiked! — and began a general glowering in the direction of the brothers, who stayed more or less out of trouble until Oct. 1.

That was when Dave Chappelle stopped by seeking some stage time and, by accident or by fortune, poked his head into the Lab instead of the Improv’s main stage.

“I’m gonna go ask if he wants to do a set,” Chris Walsh said, according to an audience member, and returned quickly with Chappelle, who gave a rapidly growing audience a stunning three-hour show, starting with “I forgot about this room.”

The audience member continues:

The staff was not too happy that he was in the annex and not the main stage. The room was just too small. They had to turn people away. Dave embraced the intimate atmosphere. He tried out some new stuff and just had conversations with onlookers, all the while keeping the audience captivated. He discussed his new life, from living in Ohio to his attempt at a comeback.

That was the end of the brothers’ time at the Improv; by Oct. 14 they were looking for a new venue and within a month had one lined up — the Unknown Theater. (The free show was listed as beginning at 8:02 p.m.)

Keeping looking here for other announced performers by the brothers. In the meantime, fans can snack on the brothers’ performance as The Ramada Boys, a video clip guest starring Erik Charles Nielson, a comic who stopped by the city’s defunct Alternative Comedy Sleepover and did a couple of episodes of NBC’s “Community” sitcom.

Or how about a clip of something the Walsh brothers can’t perform in Los Angeles? Here’s part of their brilliant theme song sketch for the Fung Wah bus company, which runs from Chinatown to Chinatown on the East Coast.