Showtime’s new series offering, “Leap Years,” seeks innovation but falls flatly into gimmickry.

The drama, which debuts at 10 p.m. Sunday, follows the lives of five New Yorkers not just in the present, but also in 1993 and 2008. (It airs regularly at 10:45 p.m. Sundays.) The show, well, leaps around among the three time periods, following the quintet’s relationships as they evolve (the relationships, not the characters, who don’t evolve all that much, unfortunately).

Instead, the characters end up just changing jobs over the 14-year span. There’s hunky Joe (Bruno Campos), the Latino lawyer turned politician. There’s nebbishy Josh (David Julian Hirsh), the wannabe developer who becomes a restaurateur. And there’s the woman torn between them, Beth (Nina Garbiras), the alluring elementary teacher turned best-selling author. Rounding out the fivesome are self-obsessed Athena (Michelle Hurd), the addicted black actress-diva, and Gregory, the gay critic, later therapist.

Sadly, these mopey co-dependents are largely stereotypes, and are hard to care about. Whiny thirtysomethings is a concept that’s been done to death. This is “Seinfeld” without the laughs or the personalities.

Since it’s created by the same team behind Showtime’s “Queer as Folk,” the vapid “Leap Years” is a big disappointment. Also its structure is anathema to casual viewers, as they’ll be hard-pressed to piece together the convoluted plot with an occasional watching. Perhaps its talented producers can right the ship, but the 90-minute premiere, directed by Martha Coolidge (“Rambling Rose”), isn’t promising.