How can you go wrong with Cole Porter's songs?

Will LeBow, Thomas Derrah, Angela Nahigian, and Karen MacDonald in "When It's Hot, It's Cole!" (Katalin Mitchell)

CAMBRIDGE - Last summer, the American Repertory Theatre took advantage of its cabaret setting at Zero Arrow Theatre and staged "A Marvelous Party," a revue of Noel Coward songs that was every bit as marvelous as its title promised. That show made it look easy - so easy, in fact, that the ART apparently decided it could do the same thing this year with Cole Porter, only without benefit of a script surrounding the songs, a director who loves and understands the material, or musical arrangements and direction that express the spirit of each song while weaving them into a coherent whole.

The result, "When It's Hot, It's Cole! A Cole Porter Cabaret," shows us just how hard effortless elegance really can be.

Yes, the songs are here, including classics from "Let's Do It" and "So in Love" to "Too Darn Hot" and "You're the Top." But the essential spirit of Cole Porter - both the effervescent, word-intoxicated wit and the achingly melancholy romance - is almost entirely absent. In its place are camped-up torch songs, hammed-up nov elty numbers, and a weirdly distant emotional tone where there should be laughter and love.

What's particularly frustrating is that the cast includes the same four singers who worked magic last year: Remo Airaldi, Thomas Derrah, Will LeBow, and Karen MacDonald. Joining them is recent ART Institute graduate Angela Nahigian and, as pianist and music director, Miranda Loud. With some exceptions - occasional pitch problems, discordant ensembles, and an almost screechy whine that Nahigian attempted for comic effect - the musical performances on opening night were generally OK.

It was what they did while they sang that was, to borrow from Porter, definitely not all right with me. Director Scott Zigler frequently leaves a singer or two sitting onstage - in the dark - to listen, or twiddle thumbs, or whatever, while another performer sings, either on the stage or off to the side by the theater's bar. He has Derrah and MacDonald move away from each other as the song's lyrics draw them closer in "From This Moment On."

He and musical arranger Peter Bayne even transform MacDonald and Nahigian into incongruous backup singers - Supremes? Pips? Sha Na Na? - as Airaldi sings lead on what we can only call "Doowop I Love You?" And even people who love medleys (who are those people, anyway?) would surely draw the line at mashing together the haunting, elegiac "Ev'ry Time We Say Goodbye" and the breezy, devil-may-care "Just One of Those Things."

But the true low point comes at the start of the second act - and not just because it's another medley, of "Anything Goes" and "Brush Up Your Shakespeare." To accompany the Shakespeare bit, Zigler projects images above the stage - starting, innocuously enough, with a familiar engraving of the playwright, but then flipping through the most "outrageous" (read: aerial, arty, in drag) moments from ART Shakespeare productions past. It's a smug, self-referential inside joke that might amuse major donors at a gala but has no place in a public show - a show that, by the way, is ostensibly about neither Shakespeare nor the ART but Cole Porter.

To be fair, the show has a few moments when the singers are allowed simply to sing the songs, and they're lovely: Derrah on "Begin the Beguine," MacDonald on "Miss Otis Regrets." A couple of comic solos also amuse, with LeBow adopting a worldly ennui for the obscure "I've a Shooting Box in Scotland" and Airaldi cutting up just enough in "Tale of the Oyster." On the whole, though, the contrast between last year's party and this year's is like night and day.