In this Late Late Show video, we learn that James was the lead singer of 5SOS - and his "drunk on power and alcohol" attitude rubbed everyone the wrong way.
In the 5 Seconds of Summer: The Early Years sketch, James explains, "I look at them as brothers. And they look at me the way Julia Roberts looks at Richard Gere in 'Pretty Woman' - 'You saved me.'"
As these things go, there's a meeting to discuss James' future with the band, as Michael Clifford, Luke Hemmings, Calum Hood, and Ashton Irwin are forced to kick him out of the group. As expected, he doesn't take it well.