Let's hear it for the ubiquitous Rob Cleveland, the busiest actor of the year. Hot off formidable back-to-back turns in "A Doll's House, Part 2" at Actor's Express and "The Royale" at Theatrical Outfit — and soon to be seen in remounts of "Doll's House 2" at Aurora and "Driving Miss Daisy" at Georgia Ensemble — Cleveland is currently providing a singular jolt of energy in Horizon Theatre's new "Waffle Palace Christmas."

Co-artistic director Lisa Adler's show is an otherwise sluggish and lukewarm holiday sequel to the company's crowd-pleasing "Waffle Palace," which was also co-written by Atlanta theater vets Larry Larson and Eddie Levi Lee. (That original comedy premiered at Horizon in 2012, and returned for sold-out runs in 2013 and 2015, too.)

This time around, Cleveland’s addition to the mix fairly well seizes and saves the day. As a modern-day incarnation of Krampus, the menacing “anti-Santa Claus” from European folklore, he wreaks havoc at a certain local diner, determined to put a damper on the seasonal good cheer — or, as he so aptly puts it, the “cloying eccentricities” — of the various people who congregate there.

Like so many co-stars in a “Hallmark movie with actors who used to be somebody” (to quote Krampus again), several members of Adler’s ensemble, reprising their roles from Horizon’s earlier “Waffle Palace,” have been (a lot) better in (a lot) better shows over the years: Allan Edwards and Lala Cochran as sundry diner customers; Marguerite Hannah as the longtime waitress and new co-owner of the place; and a particularly cloying Maria Rodriguez-Sager as two other eccentric employees.

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Actor-turned-playwright Larson originated the leading role of the dutiful John, who has inherited the franchised restaurant from his father, and he was initially cast to repeat the part for this sequel. Stepping in as a late replacement, Barry Stoltze’s John seems rather tentative and ineffectual, perhaps understandably; not unlike the rest of the production, consider his performance a work-in-progress that could still use some more work.

The comedy also introduces a few new characters: Jennifer Alice Acker plays a suspiciously loitering freelance website designer; and Markell Williams has dual roles, as both the restaurant’s new cook and a homeless veteran who pitches a tent up on the roof.

As if “stepping back in time” with its “1950s burnt bacon ambiance,” the authentic diner set is by Moriah and Isabel Curley-Clay. Aside from the appearance of Krampus, the script’s primary conflict involves John struggling to adapt to the changing times of a modern 21st-century world, when he can barely wrap his head around the concept of “social media.”

The show’s intermittent musical interludes are composed and directed by Christian Magby. The opening number is uncomfortably shaky, but a catchy second-act singalong offers an amusing riff on “The 12 Days of Christmas.” Funnily enough, insofar as the actor isn’t exactly known for his singing or dancing, in one bit Edwards delivers a memorable ditty espousing the philosophies of Kierkegaard and Heidegger.

“Waffle Palace Christmas” could use more smarts like that, instead of basically resorting to the kind of “maudlin, tear-jerking” developments worthy of the Lifetime channel, to quote the crafty Krampus again. In the end, as good as Cleveland is in the role, there’s something strangely puzzling about the fact that he’s not only the comic foil of the piece, but also its most viable voice of reason.

THEATER REVIEW

“Waffle Palace Christmas”

Through Dec. 30. 8 p.m. Tuesdays-Sundays (excluding Dec. 25); 11 a.m. Thursdays (Dec. 6 and 13 only); 11 a.m. Wednesday (Dec. 19 only). $30-$60. Horizon Theatre, 1083 Austin Ave. (in Little Five Points), Atlanta. 404-584-7450, horizontheatre.com.

Bottom line: You might feel for poor Krampus.

IN OTHER NEWS:

2018 marks 28 years collecting toys and gifts for foster kids across Georgia! Every Christmas, Clark Howard and News 95.5 and AM750 WSB join with the Georgia Department of Family and Children’s Services to provide gifts for the foster kids all across Georgia.