MOUNT VERNON — The holidays took an unexpected detour to the hoosegow Saturday night as the Dogwood Blossoms Chapter of the Sweet Adelines International presented “I’ll Be Home Out For Christmas.” The choristers were arrayed in prison stripes and billed as being in, of course, “Sing Sing” Prison.

Sue Ulrich of Columbus served as emcee, decked out as a prison guard. She set up the basic conceit of the show, which was that the chorus members were all prisoners hoping to be released for Christmas. This allowed the singers to choose a string of numbers that mixed holiday hits with other numbers reflecting the loose plot. All the songs were arranged in intricate four-part barbershop harmony, which the singers negotiated with aplomb.

The quartet Nothin’ Flat, consisting of chorus members Barb Bower, Gail Piper, Maureen Hunter and Carol Hicks, was featured in a handful of fun pieces. When one number got off to a false start, forcing the quartet to restart, Ulrich quickly scored a laugh by pounding her desk and sentencing them to “five more years.”

Much fun was had in the skillfully harmonized songs, and the chorus’ intonation was right on target. Director Donna Dudgeon achieved impressive polish, and was helped by assistant directors who took over a few numbers. Members threw themselves into each piece throughout the show with high energy and “jazz hands” standing by at the ready. One small detraction was that the amplified sound had a slight but constant ring all evening, as if it was on the verge of turning into painful feedback. Fortunately, it never did.

Special guest was the male barbershop quartet The Hot Air Buffoons, whose members hail from a range of cities as far apart as Bowling Green and West Middlesex, Pa. The Buffoons offered a well-balanced mixture of skilled singing and goofy comedy. Best of all was their routine dressed up as crash test dummies. Every time they hit a grand chord, one singer would fling his arm out in a flourish, and his fake hand would go flying into the audience. While still singing, the singer on the far end would fish out a new hand and it would be passed down the line, in rhythm, to be stuck on to replace the missing appendage.

After they ran out of hands, next came a foot, then a hook, a Statue of Liberty flame, and, finally, a rubber chicken, which the singer operated like a puppet to make it appear to join in as they sang. As anyone who has seen a lot of comedy routines over the years can attest, it takes a lot of skill to get laughs out of a rubber chicken gag these days, but these guys actually did it. Maybe it was the “high fives” between singers and the chicken.

The mens’ vocal skills are just as impressive as their comic skills, ranging from Denny Price’s sweet tenor to Randy Baughman’s cavernous bass. Mark Lang sings strong lead, as well as functioning as the “Moe” of the group, unsuccessfully trying to maintain control. Harry Haflett filled in the baritone harmonies and was endearingly hapless in the comic parts, as well.

The second half of the evening saw the chorus get released on good behavior, taking the stage in civilian evening wear. But the hijinks continued with some props along the way. The chorus was joined by Ulrich and by the Hot Air Buffoons for the closing number, a medley of “It’s Beginning to Look a Lot Like Christmas” and “Pine Cones,” which sent the audience off cheerfully into the chilly night.