When Danish alternative rockers Mew got down to working on their sixth studio album, they felt something was "missing".
That last piece to the puzzle turned out to be the band's original bass player Johan Wohlert, who had left the group in 2006 before the birth of his first child.
"That gave us the last push to give him a call," recalls the band's vocalist Jonas Bjerre, 38, of the songwriting process for the album +-, which is slated for release next month.
Bjerre, who was speaking to Life! over the telephone from Copenhagen ahead of their gig here on Monday, says: "On the last album, we felt we were lacking that band core feeling... Wohlert came over to try it out and it felt like he had never left, so it seemed natural to become a four-piece again."
Mew had recorded their last album, No More Stories... (2009), as a three-piece band following his departure.
With his return, Bjerre says the songs "got more focused", calling the upcoming album a "celebratory album" where the songs have a "triumphant feeling".
"I think it represents how the band have been feeling during the writing of the album," he says.
Mew, comprising Bjerre, Wohlert, guitarist Bo Madsen and drummer Silas Utke Jorgensen, formed in the early 1990s and found indie fame with the release in 2000 of their sophomore effort Half The World Is Watching Me.
They followed up with Frengers (2003), which received warm reviews from music critics. That year, they picked up Album Of The Year and Band Of The Year honours at the annual Danish Music Critics Awards, which recognises the best in Danish music.
Frengers was arguably the record that cemented Mew's signature sound, which mixed bombastic arena rock guitars with gentle, emotive melodies.
Following Frengers, Mew released two more albums - And the Glass Handed Kites (2005) and No More Stories... (2009).
Bjerre says the long breaks between records is due to the fact that the band usually "tours for a few years" to promote each record.
He says: "We've never been good at writing while on tour. Like, 'Let's write songs on the tour bus with a little acoustic guitar'. We're not that kind of band and we don't start writing until we're done with everything."
On their new record, Bjerre says they decided to work with other musicians, including guitarist Russell Lissack of British indie-rock band Bloc Party and New Zealand singer-songwriter Kimbra.
He says: "We've always been very reserved with the writing, we've sort of been locked away in our own world and we thought it'd be fun to have some people join in."
He adds that a year-long break from the band before they started to write and record new material helped.
"That was good because you come back to the band with new energy and different experiences and put them together into something better," he says.