On any weekday, at any given time, Embarcadero Hall reverberates with the languid, meandering lectures of its residing professor and the sighs and snores of his or her duly enthralled students. But every Friday night, from 8 to 10 p.m., the UCSB comedy troupe Improvability uses the building’s acoustics for a cause much nobler than nap time – laughter.

Students, families and a few belligerent drunks can pile to the venue, for just $3 a ticket at each week’s end to enjoy about two hours of first-rate improv. The audience, which Improvability describes as being “smart, attractive, wicked cool” and of whom “15 percent have STDs,” howls and throbs – and not the agonized kind – for the near entirety of every performance.

Improvability’s comedy is everything most humor at UCSB is not: original, spontaneous and – most importantly – funny. While the general student populous seems more or less content to exchange maimed regurgitations of “Family Guy” non sequiturs and Jon Stewart jabs, each Improvability performance is completely organic. The only scripted aspect, per se, is the predetermined choice of games for every show and their appointed rules. The games provide the troupe with a loose structure to frame their impromptu jokes and developments and save them from flailing around in a vacuum. For instance, in “My Movie, My Movie,” the players make off-the-cuff pitches for imaginary films, like “Alien vs. Predator vs. Rocky,” and then “screen” the best of them on stage. In another game, “Spelling Bee,” they form a multi-headed monster that tries desperately, and usually unavailingly, to correctly spell words suggested by the audience.

Luckily, spelling is not a criterion for comedy. Improvability’s members have a host of other talents, and their comedic styles cover a wide range, which augments the already unpredictable interplay on stage. Chris Otte, an Improvability veteran, and Tim Lamphier, a recent addition to the troupe, rarely fail to catch the audience off guard with their refreshingly oblique approach; I witnessed Otte leap off the stage as a heart-broken, suicidal duck not once, but three times in a single night. Jace Armstrong, with his impeccable timing and je ne sais quoi, somehow renders even the slightest gesture or utterance into comedy gold. And Charlie Granville, an Englishman with an uncanny appetite for Philly cheese steaks, has the acumen and linguistic agility to sustain side-busting monologues that make Americans – myself included – remind themselves of our less bright and inarticulate side of the Atlantic.

All of Improvability’s 10 members are funny in their own right but, as a group, they are hilarious. David TenBrook, the self-described “moral keel of the Improvability boat,” says that their performances are “all about synergy.” Of course there are occasional lapses in chemistry between members of the troupe, but there never seem to be any between Improvability and its audience. That is why, on a Friday night, everybody in Embarcadero Hall is guaranteed to have a good time.