Bon Jovi reveal an emotional trailer for their upcoming documentary 'Thank You, Goodnight'

"Every night was a war".

According to Bon Jovi's keyboardist, David Bryan, things were not always as rosy as they seemed within the band as they strode towards superstardom.

The trailer for the Livin' On A Prayer rock legends' documentary Thank You, Goodnight is out now - marking the first-ever official documentary to be sanctioned by the band.

The four-part docu-series will cover their rise, the fallouts, and the band's uncertain future. It is set to be a rollercoaster of emotions delving into the highest of highs and the lowest of lows.

"It was real fun. If you work hard enough, you can make it," one of the band members says during the trailer. "But it was taking a toll. It really got out of control."

Showing montages of extreme highs the band experienced during the '80s, the trailer then shows their lows currently.

One clip shows Jon Bon Jovi lying in a hospital bed, holding up a small whiteboard which has "I'm good" written on it, suggesting the documentary will focus on his recent vocal issues which plunged the rock band into uncertainty.

Thank You, Goodnight will offer new insight into Bon Jovi's past through exclusive interviews and never-before-seen or heard photos and demo songs.

"I don't know if there's gonna be a happy ending," said a voice off-camera.

The singer explained what happened to his voice during a recent appearance as a speaker for the Pollstar Live! conference.

Jon said that "one of my cords was literally atrophied" and the "strong one was literally taking what was left of the weak one. So they put a plastic implant in, and for the last two years now, I've been in this rehab, getting it back together."

He also cast doubt on the future of Bon Jovi, admitting that "if I can't be great, I'm out. And I think that the documentary that we're about to put out addresses all of that."

Despite Richie Sambora's involvement in the documentary too - who left the band in 2013 - there doesn't seem to be a way back into Bon Jovi for the guitarist, even though he's open to a full reunion for their upcoming 40th anniversary.

"There's a documentary that's being done about the band and stuff that I've participated in, and people want to come see us play, and it's going to make everybody happy. I mean, essentially, that's why you do it at this point."

Thank You, Goodnight is set for release on Disney+ in April this year.