TNT must be patting themselves on the back for being able to wrangle Eric McCormack and Tom Cavanagh to star in their new drama, “Trust Me.” They’re such instantly recognizable faces – McCormack for his eight seasons as Will Truman on “Will & Grace,” Cavanagh for everything from “Ed” to “Eli Stone” – that they might actually help get the show over the hump of being the first new TV series about an ad agency to appear since the debut of “Mad Men.”

“We’re prepared to deal with the ‘Mad Men’ comparisons,” said co-creator John Coveny, “because we’ve had them for the last year as we brought this to you guys.”

McCormack seemed stunned that anyone would make such a comparison. “Is anybody going to confuse the show with ‘Mad Men’? I think it’s a question that only comes up if you haven’t seen the show yet. Once you’ve seen them both, they’re very different shows.”

Despite having both been on NBC shows at the same time and both being Canadian, McCormack and Cavanagh had somehow never managed to work together prior to being teamed up for this series.

“I remember the first time we rehearsed,” said McCormack. “We literally had not met until the day we rehearsed the day before we started to shoot, and we did one of the scenes from the pilot together. Off the cuff, Tom threw some stuff in; I threw it back at him. We kind of looked over at these guys, and everyone seemed very, very pleased. It was one of those sort of, ‘Please let this work,’ and it was absolutely just a great chemistry…despite the fact that he’s a dick.”

Cavanagh sighed and shook his head. “You couldn’t end it on sincerity,” he said. “Did you see that? What does that say about you?”

One of the more surprising faces amongst the ensemble cast is Griffin Dunne, in the first regular series role he’s had since…well, ever, really. “I haven’t been acting and had as good a part and been involved with something as an actor like this for a long time, so I’m just completely focused on playing this guy,” he said. “They’ve written a fantastic character for me, so that’s my primary purpose. I’m always developing things and trying to find other projects to get going and something I hope to direct at the end of the season, but, really, when episodes come along and there’s something to do, there’s just so much sort of texture and character to play. It’s such a joy to be able to just do that.”

The female lead in “Trust Me” is Monica Potter, who’s kept a relatively low profile since departing “Boston Legal,” but she would be hard pressed to sound more grateful for this role. “I am so lucky to have a job,” she gushed. “I’m just very, very grateful to have a job. And I also am so lucky to be able to come to work every day and get to try new things, and I’m really lucky to work for all these people. I still don’t know everybody’s name, but…”

(As she trailed off into the laughter of the assembled critics, Cavanagh seemed impressed by her admission. “Not everybody can get away with that,” he observed.)

Michael Robin, one of the other executive producers, chimed in to assure everyone that “Trust Me” was just as happy to have Potter as she was to have the job. “One of the things I think everybody is really going to enjoy – something I didn’t know about Monica – is that she’s a master comedienne,” said Robin. “She is so great with all the comedy, and watching the three of them bang into each other in the way that you’re going to get to watch, it’s just really a lot of fun, and I get so psyched watching Monica get to just lift off in this new direction we haven’t seen much of. I really enjoy that.”

And as long as we’re into the realm of back-patting, TNT exec Michael Wright chimed in to say just how pleased he was with the show as a whole. “I think the show’s a natural evolution for us,” Wright said. “As we began getting into the series business a few year ago, it’s fairly logical to try to craft dramas that were consistent with what was already working on the network. At the time, it was ‘Law & Order’ and shows like it. At this point, as we’re trying to evolve beyond franchise dramas, what drew us to this show is what’s drawn us to the rest of the shows, and I think what makes it consistent is that all of these shows — from ‘The Closer’ to ‘Saving Grace’ to ‘Trust Me’ — is they’re meant to be built around complex, relatable central characters. There’s a relate-ability that ought to be consistent from Brenda Leigh Johnson to Grace Hanadarko to Mason and Conner. You should see yourself or people you know in these characters. So whether we’re doing a cop drama or a workplace drama, that’s the consistency beyond it: that relatability and complexity.”

Both McCormack and Cavanagh certainly seem happy with their work. “What’s been amazing for both of us is that we come across sounding a little bit corny, because it sounds like we’re towing the party line, but we’re both so happy to be at this cable network doing this show,” said Cavanagh. “It’s been great. I know you all know more about that than we do, but for us, really the experience has been genuinely…what’s the right word?

“Awesome?” tried McCormack.

Cavanagh grinned. “Awesome,” he repeated.

Lastly, in a revelation that’s rather surprising for a show created by two former ad guys, the bits that have proved hardest to write have been the ad campaigns. “Truly the most agonizing parts are coming up with a worthy commercial,” said Greer Shephard, the show’s executive producer. “In the pilot, when we handed the pilot in to TNT and Michael Wright, Michael had very few notes on the actual writing of the script, but he did turn to Hunt and John and said, ‘You could maybe come up with a better tag line.'”

“I had ten consecutive years where my New Year’s resolution was to get out of advertising, I had finally done it,” said Baldwin. “And I sit across from him, and his one comment is, ‘I wish the ads were funnier.’”

“Trust Me” premieres on TNT on January 26.