Alan Ritchson and Justin Hartley, <EM>Smallville</EM> Alan Ritchson and Justin Hartley, Smallville

On a mild November morning on the set of Smallville in Burnaby, British Columbia, Justin Hartley and Alan Ritchson are waiting for their breakfast from the meal truck. In a few hours, the two actors will join Kyle Gallner, Lee Thompson Young and series star Tom Welling to film a pivotal scene in tonight's Justice League-themed episode (airing at 8 pm/ET, on the CW). Hartley's Oliver Queen — aka the Green Arrow — is rounding up the newbie heroes to stop Lex Luthor's mysterious Project 33.1, which is experimenting on the superpowered set. On Ollie's roster are Aquaman (Ritchson), human-computer hybrid Cyborg (Young) and scarlet speedster Impulse (Gallner), a variation on The Flash. Clark Kent (Welling), the future Superman, eventually joins them for the mission on what is sure to be one of the finest hours in the 6-year-old series.

The episode marks the end point of Hartley's well-received guest arc on Smallville. He could be back later in the season, but right now he seems quite comfortable, shooting the breeze with Ritchson as they wait for their omelets.

But shouldn't there be some tension between these two? After all, it was Hartley who scored the plum lead role in the CW network's Aquaman pilot — a project that was granted a green light in the wake of the robust ratings the character brought to Smallville with an October 2005 visit. Though Ritchson, a semifinalist on Season 3 of American Idol, had delivered an energetic performance in the role, Warner Bros. didn't cast him for their proposed series, instead going with Passions vet Hartley. Alas, despite an intriguing premise and ambitious production values, the show didn't get picked up, so the Smallville producers (who had been creating Aquaman) quickly reeled Hartley back in for the Green Arrow gig.

Was Ritchson reluctant to come back to Smallville? "I wasn't at all," he says sincerely. And it wasn't awkward meeting Hartley? "There's absolutely no tension between Justin and myself," he says. "I'm happy for his success.... He's a really great guy. Business is business." Hartley also thinks there would have been room on the planet for more than one King of the Seas: "I think the character that Alan plays on this show, even though it's Aquaman, is a different character than I played in the pilot."

And perhaps in an effort to eliminate any on-set awkwardness, the dynamic duo went out for dinner the night before filming for this episode began. Hartley confirms that there was no bad blood, alternately referring to Ritchson as "great," "fantastic" and "hilarious."

Maybe instead of the Justice League they should call themselves the Mutual Admiration Society.

For more "Justice" preview, read TVGuide.com's Trivial Matt'rs blog.

Looking for scoop on TV's other super Heroes? Pick up the Jan. 22 issue of TV Guide. Also, TV Guide Channel's The 411 this week hits a Golden Globes after-party with Hayden Panettierre.

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