By James Hibberd
Updated May 24, 2013 at 09:55 PM EDT
Credit: Ray Mickshaw/FOX

After 18 years, Fox’s legendary reality chief is stepping down.

Mike Darnell, a colorful provocateur who pioneered the genre, will leave the network at the end of June.

For nearly two decades, Darnell’s shows have generated ratings, headlines and occasional outrage. In the late 1990s, he helped kick-start contemporary reality TV through a series of attention-grabbing specials, such as World’s Scariest Police Chases, When Stunts Go Bad, Close Calls: Cheating Death and, of course, When Animals Attack! (and don’t forget the exclamation point). As the reality genre began to take shape in the wake of CBS’ Survivor, Darnell launched shows like Temptation Island, The Simple Life, Joe Millionaire and My Big Fat Obnoxious Fiance, along with long-running hits like American Idol and Hell’s Kitchen.

Sometime his efforts backfired into controversy, such as the special Who Wants to Marry a Multi-Millionaire? and the series Married by America, the latter drawing the wrath of the FCC. And there were plenty of critical targets too, like lie detector quiz show The Moment of Truth and the ultra-extreme makeover show The Swan.

But regardless of how you felt about his shows, Darnell was bold and unique. A gravel-voiced cowboy-hat wearing high-energy executive who played the piano in his office and loved-loved-loved a wildly popular genre of TV that few others seemed to respect. He always strove to push the envelope and try concepts and twists that no one had attempted before, sometimes at the consternation of his bosses (he famously once wanted to crash a large commercial aircraft in the desert). And then there’s his conversational, audience-challenging show titles: So You Think You Can Dance? Are You Smarter Than a 5th Grader? Don’t Forget the Lyrics! Darnell always knew how to get your attention.

Darnell will exit as the crown jewel in his tenure, Idol — which helped keep Fox as the top-ranked broadcaster for eight years — undergoes a judges panel overhaul following a rough season in the ratings. He hopes to have a new panel signed before he leaves. first reported the news.

“I’m extremely grateful that Fox has offered me a new long term contract (and anyone who knows me won’t believe I’m saying this), but I’ve decided it’s time for a change,” Darnell said in a statement. “With my current deal ending in June, and having been here for 18 years (kind of a record in Hollywood), I had to make a decision: either stay (and basically admit to myself I was going to retire at Fox…not a terrible choice) or leave and try something new. I’ve been in ‘Reality’ since before it was even called that, and it has truly been an amazing ride. However, the world has changed drastically over the last few years and now with hundreds of channels and limitless ways to watch television, I’ve decided this was the perfect time to take advantage of the rapidly changing marketplace. To say I am going to miss everyone here and that the people at Fox are like a family to me would be the understatement of the decade. I have so many people to thank (and I will call all of you!), but first and foremost, I want to thank Kevin Reilly, Peter Rice, Chase Carey and Rupert Murdoch for all their amazing support over these many years.”

In a rare inclusion for a Fox press release, News Corp. Chairman and CEO Rupert Murdoch issued a statement as well: “Mike took risks at a critical time and was a pioneering force in shaping the reality programming genre that exists today. He’s a smart and fearless executive who will be missed.”

Darnell hasn’t yet decided his next move, though a shift into producing shows is one obvious path.

Regardless of whether Fox’s reality efforts perform better or worse in the ratings after he goes, one thing is for sure: Network TV will be a less interesting place without him.

“It’s very bittersweet, but it just felt like I needed to make a move,” Darnell told EW. “The wild west that was created here doesn’t exist anymore. There’s so much else out there now.”