There was a moment when “Smallville” was, improbably, one of the best unsung programs on television — smart, exciting and surprising, with a topnotch cast, including (perhaps particularly) the adult roles.

As the show begins its 10th and final season, however, that moment has long since passed.

“Smallville” has hung on this long because the WB-turned-CW kept needing it, international sales were strong and star Tom Welling was willing to keep playing Superboy into what’s by now approaching super-Middle
Mack1 Age.

But the series that once billed itself as “No tights, no flights” has spent too many years spinning its wheels to avoid stepping on Superman mythology, while coyly dancing up to that line. Introducing other members of the DC Comics universe (the best being Justin Hartley as Green Arrow) and dancing around the absence of Lex Luthor since Michael Rosenbaum’s departure could ultimately carry the show only go so far.

After watching a screener of the season premiere — in which Clark Kent’s place on Earth is as much Christ-like as Kryptonian — it’s hard to imagine how they’re going to continue milking that for another whole season. But having been there at the beginning, I feel sort of obligated to see the finish. Just wake me when it’s (almost) over.