Ross Kemp has accused the old 'EastEnders' boss of working the cast "into the ground."
The legendary actor - who portrayed bad boy Grant Mitchell in the long-running soap - thinks Sean O'Connor made the right decision by quitting his executive producer role, a position he's only held for a year, last month because he was destroying his staff.
Speaking to The Sun Online, he said: "He reminded me of a sort of schoolteacher of a kind of third-rate public school.
"That's not really what you want for the cast of 'EastEnders'. You write it well, you cast it well and you do the right things -- and you don't abuse certain members, i.e. you don't work them into the f****** ground, which is what happened. The cast are earning more than the executive producers, which makes it a very odd power balance, doesn't it?"
The 52-year-old star has played Grant on and off since 1990 and is thrilled his alter ego hasn't been killed off as he would love to go back to the soap at some point and work with Steve McFadden, who portrays his on-screen brother Phil Mitchell, again.
He explained: "It's great they haven't killed Grant off. I'm very happy the Mitchell brothers are still alive and hopefully they will ride again at some point."
Meanwhile, some fans have claimed Sean's decision to kill off Ronnie and Roxy Mitchell - played by Samantha Womack and Rita Simons - earlier this year caused a drop in ratings.
But, although Samantha is devastated she can't ever return to the show, she doesn't think Sean - who took over from Dominic Treadwell-Collins in 2015 - is entirely to blame.
She said recently: "I'm always wary of making one single person a scapegoat. Ideas are brought to him too. It's easy to pin the blame on one person, I don't think it's helpful."