For a perfectly delightful trip down memory lane for people of a certain age, there’s nothing quite like the adorable musical “Forever Plaid.” 

San Francisco’s 42nd Street Moon’s third show of its 31st season is a nicely satisfying production starring four delicious singers (who are no slouches at comedy, either) and two stalwart musicians. 

The revue, with a book by Stuart Ross and a roster of pre-rock and roll hits from 1950s-60s, was an off-Broadway hit in 1989. Today, a community and regional theater favorite, it’s a true celebration of tunes from the mid-20th century and an homage to the clean- cut harmony-heavy boy bands of the fifties. 

From the opener “Three Coins in the Fountain” to the closing “Love Is a Many Splendored Thing,” there isn’t a clunker in the tuneful lineup. And the four men in the undiscovered quartet, a Pennsylvania outfit called Forever Plaid that plays weddings, lounges and bowling alleys, do the songs justice. 

Tenors Edu Gonzalez-Maldonado and Justin P. Lopez, are, respectively, stepbrothers Jinx and Sparky, baritone Kevin Singer is Frankie, and bass Matt Skinner is Smudge. Bassist Kyle Wong and pianist Tim Fletcher (also assistant music director) round out the performers. They’re led impeccably by Daniel Thomas, the troupe’s artistic director, handling musical and stage direction, and there’s fun choreography by Brittney Monroe. 

They make a stellar team, and it’s no surprise, given Thomas’ familiarity with the show. He says in program notes that this production represents the 13th time he’s been involved with “Forever Plaid” be it acting (he was directed by Jason Graae, the original Sparky in 1989), directing or producing. 

The thin plot revolves around a fantastic event, Forever Plaid making what Sparky calls “the biggest comeback since Lazarus.” The story begins with narration describing how the boys perished in a collision on Feb. 9, 1964: While driving to a gig, their vehicle was broadsided by a bus carrying Catholic schoolgirls to see The Beatles on “The Ed Sullivan Show.” 

But, through the magic of theater, they return to life, and are offered the opportunity, 60 years later, to share their harmonic glory. They’re nothing short of a smashing success. 

L-R, Edu Gonzalez-Maldonado, Kevin Singer, Matt Skinner and Justin P. Lopez are the tuneful quartet in “Forever Plaid,” presented by 42nd Street Moon at the Gateway Theatre in San Francisco. (Courtesy Ben Krantz) 

They display versatility with everything from swing and boogie-woogie selections (“Gotta Be This or That”/”Undecided”) to Latin (“Perfidia”) to work songs (“16 Tons”/“Chain Gang”) to calypso (“Day-O,” “Jamaica Farewell” and the sing-along “Matilda”). 

More audience participation comes with “Heart and Soul.” As Tim takes a union-required break, an enthusiastic theatergoer is invited to join Sparky at the piano onstage to pound out the famed beginners’ duet on the Hoagy Carmichael tune.   

Most riotous, though, is the three-minute Ed Sullivan sequence in which the fellas become the variety show’s popular acts (Topo Gigio, the Singing Nun, plate spinners, jugglers, etc.) as Jinx belts “Lady of Spain.” 

Things slow down for the lovely a cappella plaid-forward “Scotland the Brave” before the fellows know they’ve truly made it in “Rags to Riches.” 

“Forever Plaid,” in great hands of 42nd Street Moon’s talented cast and crew, offers a bounty of tuneful riches.   

42nd Street Moon’s “Forever Plaid” continues through May 5 at the Gateway Theatre, 215 Jackson St., San Francisco. Tickets are $25-$70 at 42ndstmoon.org or (415) 255-8207.