“Glee” star Matthew Morrison smacked of Justin Timberlake at the beginning and Gene Kelly at the end of his Friday concert with the National Symphony Orchestra’s Pops series. Neither persona was terribly convincing, despite Morrison’s unflagging enthusiasm and boyish charm.

That heartthrob quality was immediately on display as Morrison, 35, took the stage in a tux and a hipster’s hat, unabashedly dancing like a hep-cat wannabe during the instrumental breaks in an up-tempo “It Don’t Mean a Thing.” His range was easy and his singing was smooth, but not nearly as zesty as what conductor Steven Reineke and the NSO were serving up. More notable, for the wrong reasons, were Morrison’s spin moves and flourishes with that quickly annoying Rat Pack hat.

Nothing much came of the simmering “Luck Be a Lady” either, slowed to a sensual beat that felt like vintage Havana after dark. The arrangement was appealing, but it didn’t frame Morrison’s crooning in a particularly revealing or effective light. Not until a moody “Come Rain or Come Shine” mash-up with “Basin Street Blues” could you hear something that rose above the standard of too-easy listening. Morrison again took a harmlessly silky approach, but eventually — briefly — his voice flushed with true melancholy and passion.

It’s worth remembering that, pre-“Glee,” Morrison had a good decade on Broadway: He played the original Link Larkin in “Hairspray,” he earned a Tony nomination as Fabrizio in “The Light in the Piazza” and he performed as Lt. Joseph Cable in the Lincoln Center Theater’s ravishing revival of “South Pacific.” His new album, “Where It All Began,” is full of show tunes and standards, and they drove Morrison’s set list, yet they didn’t plant a firm identity on the singer. Even “Sway,” a mambo hit for everyone from Dean Martin to Michael Buble, was performed capably and efficiently — another bauble Morrison rendered with facility, but not with authority or a style of his own.

The NSO’s best offerings without Morrison showcased Nelson Riddle’s arrangements for “I’ve Got You Under My Skin” and George Gershwin’s “Three Preludes.” With Morrison and “Glee” pianist Brad Ellis, the orchestra supplied as much verve and panache as the arrangements allowed. But the star, who concluded by hoofing with an umbrella for “Singin’ in the Rain,” too often seemed to be dancing in borrowed clothes.

Matthew Morrison performs at the Kennedy Center. (Jon Willing)

Pressley is a freelance writer.