The year is 2013. Popular culture's monopolising influence continues to be unshakeable. In the year that saw Beyoncé play the Super Bowl (a performance that saw hundreds of thousands of unflattering images and GIFs circulate Tumblr for the LOLz), and Blurred Lines infiltrated every possible channel, there seemed to be no place for pop punk - let alone its undiluted predecessor.

In 2008, following the commercially and critically panned 'Folie Á Deux', emo kings Fall Out Boy hung up their fedoras and bat-emblazoned bass guitars respectively, in order to 'regroup'. Bloodied and bruised from the backlash, it came at a difficult time - following a greatest hits album and a co-headline tour with pop-punk overlords Blink-182.

Patrick Stump, Pete Wentz, Andy Hurley and Joe Trohman stepped out of the bubble of the band to pursue side projects, with varying levels of success. Pete and Patrick, probably the two members that needed the break most, (they hold the record for completing the most interviews in 24 hours), found the hiatus inevitably did more harm than good.

Wentz' electro project Black Cards suffered delay after delay before the group ran itself into the ground. Stump's entirely self-produced, self-recorded and self-funded solo album 'Soul Punk' saw him be verbally abused at shows about his weight and his former group.

Four and a half long years passed for fans, lamenting their loss on LiveJournal and the now-defunct falloutboyrock.com forums. But it was simply to be the calm before the storm.

The band returned in suitably melodramatic (and gloriously emo) fashion in 2013 - black and white shots of the band in studio, Instagrams of the foursome burning their old material - at one point, Wentz simply tweeted 'we miss you'.

The landscape had changed. The industry was continuing to shift away from anything that smelled of guitars. With a fire under foot, however, Fall Out Boy changed with it. 'Save Rock And Roll' was not the saviour of a genre, but an acknowledgment of how it can be reborn, featuring collaborations with Courtney Love, Foxes, and Elton John. The album went straight to number 1 in the US, with lead single My Songs Know What You Did In The Dark. It was an exciting period for the band: some publications going as far as referring to it as a 'renaissance era'.

Success, pre and post-hiatus are two different beasts to Wentz. "Hopefully, there's a humility there now that there may not have been starting out", he says. "We've seen the highest highs and we've seen some lows. I think understanding that life's a rollercoaster, and like, you really gotta put your hands in the air and just appreciate it."

Wentz also suggests that there has been a lot of growth between their stratospheric ascent of the charts with 'From Under The Cork Tree' to present-day, adult-sized Fall Out Boy. "The trajectory we were on last time made it really hard to get any perspective. It's like, 'oh, you're on TRL', and then you're on a jet, and then you're in this random country ... It's hard to appreciate what you're going through - it's too much, too fast."

One thing that has remained consistent is the band's mammoth work ethic. Fall Out Boy's sixth studio album 'American Beauty/American Psycho' was released in January - less than two years after 'Save Rock And Roll'. Even more ambitious than its predecessor, it features samples from Tom's Diner to the theme song for The Munsters.

"When we create albums, they all have an independent visual that goes along with them in my head. 'Save Rock And Roll' was supposed to be a non-homage to rock and roll, and the idea of rock and roll. 'American Beauty/American Psycho' is a different animal - it's more of a take on a modern love story. We're all cell phone obsessed now and it's just interesting to me. How do you fall in love with the glow of a computer screen?"

Not simply running on the adrenaline spike that was the huge success of Save Rock And Roll, Wentz admits it was a conscious decision to head straight back into the studio.

"We basically churned the records out back-to-back. You see these rappers and DJs who are able to write and record stuff overnight. Bands have never been able to do that. We were kind of like, 'can we operate on this timeline that pop culture operates on right now?'"

Writing and recording took place while promoting the previous album, and in the midst of a co-headline tour with Paramore. "In that way, it was the best, we recorded in hotel rooms, and backstage at festivals. Our sanity was a little frayed around the edges afterwards, but it was still a cool experience."

Fall Out Boy have spent the majority of their adult lives touring. They are about to embark on the European leg in support of'American Beauty/American Psycho', having just finished touring with rapper Wiz Khalifa across America on the 'Boys Of Zummer' tour. It was an interesting collaboration that, initially, was questioned by fans.

"Wiz, in some ways, is in a similar boat to us. He has a foot in hip-hop, but he also has a foot in pop. We reached out to him, and he was open to it."

"Being honest, it was probably one of the most fun tours we've ever done. Wiz was a pleasure to be on tour with - such good vibes."

The backlash to the collaboration was a surprise to Wentz - understandable, given the band has worked with hip-hop heavyweights 2 Chainz and Lil Wayne previously. Jay-Z even did the intro for third album 'Infinity On High'.

"The amount of times we've spoken about the influence of hip-hop on us over the years ... It surprises me that people are still surprised," he laughs.

The band have shown a new knack for musical experimentation, whether it's their last two studio releases or their flirtations with hardcore/punk stylings on 2013's 'Pax AM Days' EP. Who's to say the band couldn't release a rap/rock hybrid?

"We're not gonna ever be rappers", Wentz laughs, "But we're open to doing remixes."

"The sky is the limit I think: genre means so much less now. The way we consume music now is great - you're able to just stream songs constantly. People are more open to different kinds of stuff. Kids just like songs now, so we're still open to experimenting."

The European tour focuses on the album thematically, but they have a lot more to bring to the table, given the venue upgrade from two years ago to the 3Arena.

"We weren't always able to bring the full production that we had. This time, we're able to bring the exact same set we'd deliver in the States. I'm stoked! We want people to see the show at its best, biggest version."

Fall Out Boy won Best Rock Video - beating out Hozier - at last month's MTV Video Music Awards - an award that was not televised. Rock and alternative genres are continuing to be under-represented at award shows such as this - something which Wentz openly acknowledges but is quick to play down.

"We've been doing this for 15 years. Nobody wants to hear a rockstar complain about awards shows."

He continues, "to me, it says more about the state of rock music. We're grateful to be a part of the conversation, but I don't know if we have anything important enough to say during the main show!" he laughs, "I don't know. Whatever."

Wentz highlights another difference between the band then and now - his ego.

"Twelve years ago if that had happened at an awards show, I probably would have freaked out and had a moment about it. But we're not that band anymore."

In support of 'Save Rock And Roll', Fall Out Boy released a video for every song on the album, calling the project 'The Young Blood Chronicles'. Their videography is elaborate and often unusual - but Wentz still reckons they're a bit away from receiving MTV's Video Vanguard award.

"Honestly, it is the goal. We grew up in the MTV generation when Axel Rose and Michael Jackson made these epic videos. Pretty much since the beginning of our career, we've been trying to do that, starting with the Sugar We're Going Down video, right through to Dance, Dance and A Little Less Sixteen Candles ... They've all been event videos. We always want to make someone feel the context of the storyline that you couldn't represent through just the music alone."

"We're a long way from a Vanguard award though. I thought it was super appropriate to give it to Kanye. He's had a huge impact over the last decade."

The award-winning video for Uma Thurman features a reference to Alabama's law banning same-sex marriage, which sees Wentz destroying a truck with the article number written on it.

"I feel it's a responsibility as a human being to do stuff like that," he says, "There's a difference between having an opinion and standing on the wrong side of history. When we look back on slavery or apartheid or Jim Crowe, we'll question, like, 'why weren't these people speaking up?' When it comes to legislating love, it's something I think we should stand up for."

Wentz is aware there's a limit when it comes to soapbox rants, mind.

"I have plenty of other opinions. But it's just one guy's opinion. I can't cram them down people's throats. At the end of the day, I'm just a guy in a band."

Bands like All Time Low, 5 Seconds Of Summer - hell, maybe even One Direction - look set to replace Fall Out Boy at the top of the pop-punk food chain, should they ever decide to call it quits. But they are not as much competition to Wentz, as they are peers.

"I appreciate that there's a whole new generation of artists with entirely new fan bases and I understand what they're doing and where they're at. We're not at that point anymore, and we don't need to be doing as much of that stuff ."

When he's not being one of the most famous bassists on the planet, Wentz invests himself in other artists. He re-launched his label Decaydance Records in 2014, under the new moniker of DCD2 Records.

"That's like, the biggest passion project I have outside of Fall Out Boy, and it's a lot of fun to do. I really like working behind the scenes with other artists and seeing them succeed, knowing their vision ... As an artist, I think it's just as important to protect other artists. Seeing Panic [Panic! At The Disco] do what they do and Travie McCoy ... They've just got this hungry young thing going on."

"Lolo just put out an EP on the label with some of the best lyrics out there right now. Our first artist from the UK, Charley Marley, his songs are completely bonkers. They're not in the same lane as anything else - maybe there isn't even a lane for us. We just find artists we love and work with them."

At the time of the interview, Wentz admits he's enjoying the down time, with eldest son, Bronx, on a half day from school. At several meet and greets, including one at Tower Records last year, Wentz and his fellow bandmates promised teary-eyed fans that they would never, ever go on hiatus again. Were they empty promises? Surely they must accept at some point that the show can't go on?

"Everyone's grown up a little bit. Three of us have kids. I really appreciate all the time that I've spent with my family. But I also appreciate that the fans are still letting us do this."

"It's harder to be away from your family, especially as they're growing up. At the end of the day, there are new generations of new musicians coming out that have different ambitions to us. I look at bands like Metallica and Coldplay and Foo Fighters - they've figured out how to gracefully become 'the next thing'. That's something that, as a band, we're still trying to figure out."