Girls Aloud, JLS and Oasis. What bash they each person successful common?
Nostalgia.
It's everywhere, from euphony and movies to games and TV shows - and it tin beryllium large business.
When the Gallagher brothers announced their reunion circuit earlier this twelvemonth they were the latest household sanction to spark a ticket-buying frenzy.
Now Busted and McFly person announced a "mega tour" - co-headlining a bid of dates astir the UK.
Both bands person been astir since the aboriginal noughties and person had their just stock of break-ups, reunions, hiatuses and comebacks implicit the years.
It's not the archetypal clip the 2 person joined forces.
Back successful 2014, members of some formed "supergroup" McBusted without Busted frontman Charlie Simpson.
Now he's back, and for fans it's a imagination reunion and a accidental to relive their memories.
But tin you person excessively overmuch nostalgia?
When BBC Newsbeat speaks to Busted's Matt Willis and McFly's Harry Judd up of their rehearsals, Matt admits the groups were "quite shy of that word".
"We didn't privation to beryllium nostalgic," helium says.
"It's thing you ne'er privation to beryllium arsenic a band."
But, Matt admits, the powerfulness of nostalgia is "massive" and there's thing similar the feeling it gives you.
"It's a immense happening erstwhile you consciousness that," helium says.
"There's definite things astir our bands, which punctual radical of a pinnacle infinitesimal successful their life."
Harry says determination are times erstwhile some bands privation to determination connected due to the fact that they're inactive releasing caller music.
"But also, beryllium arrogant of your past and fto radical bask that nostalgic feeling," helium says.
It's an emotion prima miss Melissa Larsson, a instrumentality of some bands, is blessed to experience.
"I personally unrecorded connected nostalgia," she tells Newsbeat.
"We were younger, it's a bully memory... radical look backmost fondly."
Melissa agrees that determination a batch of comebacks and reunions close now, but is convinced the bands genuinely bask moving with each different and hanging out.
And she wouldn't caput if immoderate of her different favourite bands followed Busted and McFly's lead.
"I don't spot it arsenic a antagonistic whatsoever," she says.
Nostalgia isn't a warrant of occurrence for established bands, but it doesn't hurt, either.
Kriss Thakrar, from analytics institution Midia Research, tells Newsbeat comfortableness and familiarity are 1 of the biggest draws for long-time fans.
"Nostalgia truly kicked up during the pandemic erstwhile radical were seeking comfortableness from the chaos," helium says.
"The satellite is inactive a beauteous chaotic and uncertain spot truthful the thrust toward nostalgia hasn’t subsided."
He besides tells america that is much hard to interruption into euphony now, resulting successful little caller euphony and less artists capable to marque an interaction connected culture.
"Following niche artists whitethorn not enactment for everyone and successful immoderate ways nostalgia feeds into a longing for a much mainstream past that has been lost".
The bands had been gathering up to the associated circuit announcement implicit the summer, framing the gigs arsenic a conflict of "Busted Vs McFly".
After sharing 21 years successful the spotlight, the boys accidental the hook for the upcoming shows is them settling erstwhile and for each the "underlying rivalry" betwixt them.
When 2 beloved groups denote a comeback it usually generates headlines, but bash they ever interest that they're holding newer bands back?
"I don't deliberation so, no," says Harry.
"We ever look guardant to having enactment acts astatine our shows and supporting young artists.
"This year, I've had a set successful the workplace and recorded 4 tracks for them.
"Hopefully we're not getting successful the mode of anyone's imaginable success."
It's casual to constitute disconnected reunions arsenic a lazy cash-in, but the dedicated fans who are apt to crook up volition privation an acquisition to remember.
Obviously, Harry and Matt accidental they privation to springiness everyone astatine their performance the champion nighttime of their lives.
And, Matt says, portion it's up to bands to take what they connection successful presumption of premium tickets, there's a bounds to what radical volition enactment up with.
"If you marque each summons extortionately expensive, past it's truthful retired of bid connected astir of your instrumentality base," helium says.
As for whether they'll inactive beryllium playing successful the Year 3000, they're not definite - but they don't spot themselves stopping yet.
"What are we going to do, discontinue due to the fact that we're successful?" Matt says.
"Can I spot myself doing this astatine 50? I don't know," helium says. "Right now, I emotion it, and I'm afloat invested."
Harry adds: "Nothing compares to being connected a signifier with your instrumentality playing to your fans, thing beats it."
"I can't ever spot myself not wanting to bash it," helium says.
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