All My Chemical Romance guitarist Frank Iero needed was one week — two days, even — to help save one of the most promising bands he's heard in a long while: his new side project, Leathermouth.

The way Iero recalled it, Leathermouth formed in a very natural and organic way. A couple of his friends, who had been in other bands, were thinking about starting something. They'd already written and made crude recordings of three songs, which they'd played for Iero in one of their cars one night, not long after My Chemical Romance had returned from touring.

"I was like, 'Wow, this is really good,' and from that second, I wanted to be a part of it somehow," Iero told MTV News. "But I had too much sh-- on my hands. So they were like, 'Oh, well, we have this friend who is going to try to sing, and we'll see how it rolls from there.' I was like, 'All right,' because I have a label, and I was thinking maybe down the line, if it works with the vocals, maybe I can sign it and be involved that way."

My Chem hit the road again not long after and returned a few months later. Iero checked in on his pals. "I asked, 'Hey, how'd that band go that you guys were working on?' And they said, 'Well, he never wrote any lyrics, so we're not going to do it.' "

Iero was stunned. "I said, 'Are you f---ing kidding me? Give me a week. I'll write some lyrics, we'll rent a practice studio and see what happens.' And that's how it went down."

Iero, who has been involved with many bands (Pencey Prep, Hybrid, Sector 12, I Am a Graveyard, the Pole Smokin' Five, Give Up the Ghost, Reggie and the Full Effect and a Cure tribute band called Love Cats) but never as a lyricist. So being the face of Leathermouth was going to be a change of pace for him. He wrote all the lyrics in a week. "Two songs on the record, one's called 'Murder Was the Case They Gave Me' ... and the other one's called 'Bodysnatchers Forever,' and it was weird, man. I was sitting in my apartment, playing the songs, and the words kind of came to me, and I was really proud of them too."

Iero had never felt the urge to pen prose for any of his bands' songs before, because he said he was "always very fortunate to be in bands with people that I felt were very poetic. I always felt like the voice that I would put across would be through the music end of it. The music end was kind of taken care of [with Leathermouth], so I did the lyrics."

Iero said some people think the lyrics — and, in small part, the songs — were inspired by 1980s hardcore. And he doesn't deny it. But he thinks his words were more inspired by film. "I think, more so, it's '80s horror movies, as opposed to any kind of music. Growing up in that time, it's all I watched as a kid, so everything I do is influenced by that in some way. It's weird: The lyrics I wrote are really ... they go through experiences that are going on in the world today, but really through '80s horror-movie imagery. I don't know if that makes sense."

Of course it does.

But people coming to Leathermouth expecting it'll be My Chem-esque are in for a rude awakening.

"I think that people that get into Leathermouth because of my past bands and stuff like that, I think they'll be kind of bummed out, if that's why they're into it," Iero explained. "But it's definitely a lot different, and it's really fun for me, man. It's really cathartic and just a great experience."

Iero also shrugged off the suggestion that this new band has a very metal kind of sound. He said Leathermouth is "just dirty rock and roll." Live, "It's just a lot faster."

Leathermouth's debut LP will be in stores in January, through Epitaph. Iero said he initially wanted to release the record on his own label but scratched it — with good reason.

"With the constant, grueling schedule of My Chem and the other bands on the label, I didn't want it to fail because I didn't have the time to do it," he said. "I have a really hard time promoting myself. I like to do a lot of creative things, but as far as telling people, 'Hey, this is really good — check it out,' I'm not good at. So, I decided, 'Let me just do the record, finish it and give it to a label and just see what happens. Let it fail on its own merit.' Plus, ever since I was a little kid, I've wanted a record out on Epitaph."

At some point around the holidays, My Chem, who have been on a bit of a break, will reconvene, and Iero hopes to tour with Leathermouth between stints with Romance — which is obviously his first priority.

"We're just trying to get our schedules together so we can get together and write," he said. "We're trying to do something very natural. If we get together and nothing comes out, perfect — who cares? If we get together and a record comes out, you never know."