Denis Leary, <i>Rescue Me</i> Denis Leary, Rescue Me

There's something different about Rescue Me this season that we can't quite put a finger on.

Maybe it's the complete creative rejuvenation of the show after a long, 18-month hiatus. Maybe it's the addition of the shockingly grotesque, wheelchair-bound Dwight, played brilliantly against type by guest star Michael J. Fox. Maybe it's that the show returned its focus to 9/11 and its lasting effects on the firefighters. Or maybe it's just because Season 4's look at a sober Tommy Gavin was a bit of a stinker.

If you ask Rescue Me's creators, they'll agree with most of all of that.

"We work in a vacuum," star and co-creator Denis Leary tells "It's impossible to tell what the audience or critics will think. Last season, we investigated places that we had to go, specifically with Tommy being sober. But it's not until it's out there that you get the reaction where people go, 'Y'know, it's really dark.'"

But dark isn't the word co-creator, writer and director Peter Tolan would use to describe Season 4. His word? Letdown. "The fourth season had its pleasures, but it was certainly not up to snuff, in my opinion, with what we had done in the previous years," he says. "We just sort of lost focus, the stories weren't as solid, and the storytelling, I thought, was a little weak. And many people noticed it. Because of that, I said to the guys that when we come back, we have to come back firing on all cylinders — we have to come back at 150 miles per hour and not stop."

And that's what they've done. This season — which reaches its halfway point Tuesday — has already seen Tommy dive headfirst back into the bottle and get caught between two lovers. Daniel Sunjata's Franco has spoken his mind about 9/11 conspiracy theories, despite the backlash of his fellow firefighters, and Steven Pasquale's Sean Garrity is, in his 30s, fighting cancer while keeping it a secret from the FDNY.

So how do you make sure a horny, pill-popping paraplegic love interest for Tommy's ex-wife stands out among all those goings-on? You stunt-cast an '80s nice-guy icon who's looking to try something new. "We wanted to come up with a guy that was in Tommy's wheelhouse, but was — like Tommy — so self-centered and self-absorbed and addicted, that he literally wouldn't care who Tommy was or be intimidated in the slightest," Leary says of Fox's character.

But, in fact, it was Fox's performance that intimidated Leary. "He certainly brought an energy to [the show]," Tolan says. "Denis was maybe a little uncertain. He's known Michael for a long time and was sort of wondering what we were going to get. The first day that Michael came in, he scared the s--- out of Denis, in terms of the character and all the choices he made. Denis was like, 'Jesus Christ, I've got to step it up if I am going to keep up with that.'"

Leary responded brilliantly, delivering one Emmy-reel scene after another, none greater than Tommy facing all his ghosts over a glass of vodka in an empty bar. Leary and Tolan both say Tommy's stirring "what do you do after?" speech was a by-product of improvisation on the set, a regular occurrence.

But do they think that improv session will lead to Emmy gold? Leary, who has been nominated for the show three times for writing and acting, plays off the notion. "As a producer, I see that as great advertising and influence for the show," Leary says. "But then there's the other secret evil part of me.... I'm watching these guys that I know win, and I'm like, eventually I'm gonna have to steal one of these things. I told Mike Fox, 'If you get nominated and win this year, I'm just going to come over to the house one night for dinner. And you're going to wake up the next day and say, "Wait, didn't I used to have six Emmys?'" Five years from now, nobody would actually remember that I didn't win. They're going to see the statue at my house and say, 'Oh yeah, I remember that year you won. That was a great speech.'"

Tolan, however, thinks it's the show itself that might keep Leary from making that speech. "I hope he wins because the body of work is that impressive and transcends the problem that our show has with the Emmys: It's neither fish nor fowl," Tolan says. "It's a really funny, dramatic series, and I think the Emmy voters don't know what to do with it. So, I don't hold out much hope, but he deserves it. A lot of people on that show do, but we're never going to get the recognition, which I accept."

Even with the critical buzz surrounding the show, many of the actors have hinted that the 18-episode sixth season FX has ordered might be the series' last. Leary says it might last longer; Tolan says he's ready to let it go. Both men say they know where the show ends. Naturally, though, they aren't saying.

"I've pitched three times the idea of Tommy getting killed before the show ends," Leary says. "Of course, it's not that Tommy wouldn't be there, because on this show when you die, generally speaking, your part usually gets bigger. But we have a place to go."

Tolan resists the idea that the show is heading to its darkest depth. "There's always going to be dark s--- on Rescue Me," he says. "But the beginning of next season is going to put Tommy in a situation that he's never been in before and that we've never seen [Denis] play. And it's not necessarily dark."

And if it is the end? Fine, Leary says.

"I think all movies should be about 90 minutes long, theater should end at 10:30 instead of 11, and TV shows should get off the air before you want them to," he says. "It's a strange place to be because we feel like we have a lot places left to cover. But I want the audience to feel like they wanted more."

And maybe that — the desire we have to see more of these stories — is what's different this year.

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