Michael Stewart and Cy Coleman's relic from 1977 carries with it a musty attic air, though any treasure hunter can attest to the joy of finding a vintage gem packed in the cedar chest. And it seems this particular fashion understatement is making a comeback.

Between Boeing Boeing, The First Day of School, Hunter Gatherers, and this, Philly's artistic directors seem to have one thing on their minds right now.

I Love My Wife is probably the lightest entertainment among the, um, orgy of offerings. Two young couples from Trenton (Trenton!) decide to get with the "today people" and try out some free love. They're all best friends, and certain spouses are more willing than others, but encouraged by groovy Free to Be You ditties such as "Love Revolution" and "Everybody Is Turnin' On," rest assured, a good time is ultimately had by all.

Director Tom Quinn encourages his cast to relax and go with the flow. Each of the quartet - Elizabeth McDonald's feisty Cleo, Meghan Heimbecker's down-to-earth Monica, Bob McDonald's uptight Alvin, and Joseph Michael O'Brien's swingin' ladies' man Wally - gets to camp it up in costumer Brian Strachan's gloriously ugly '70s attire. John Hobbie's set captures the seizure-inducing design that characterized the era, a floor of bright Twister circles coexisting uneasily with a pea-soup-toned background.

Though Christopher Tolomeo's musical direction is the production's weakest element, that's almost beside the point. Instead of complementing the action, the onstage band competes with the cast for audience attention. Samuel Antonio Reyes' choreography occasionally suffers from a similar effect, particularly during the song "By Threes," during which Alvin and Wally become entangled - not in a good way - playing dueling air keyboards.

Nonetheless, this cast is committed to conjuring a late-'70s sitcom vibe with the audience filling in the laugh track. Jokes are corny, sight gags easy (from cherry-red platform shoes to couples cavorting under a tented sheet), and delivery earnest.

This is a nostalgia trip with seat belts, more Aaron Spelling than Norman Lear, and all four actors happily take you there and deliver you back home safely, dignity mostly intact.