The original cast of "It's Always Sunny in Philadelphia"  SOURCE: Jordan Reid's blog

For many young actors, the thought of landing a hit sitcom is the dream. Years of steady employment, massive wealth and fame, and creating a character embraced by millions of people? It doesn’t get any better.

Yet, every now and then, a “Pete Best story” emerges. Below, a handful of actors who got a sniff of sitcom fame — only to quit, be fired or replaced just as the show was launching into the stratosphere.

RELATED: ‘It’s Always Sunny’ fan theory: Is Dennis Reynolds a serial killer?

Tales of tragedy, or inspiration? Read on, then decide for yourself.

‘It’s Always Sunny in Philadelphia’

Recently, former actress Jordan Reid published a moving blog entry detailing her equal partnership role developing, starring in and getting subsequently fired from the hit FX show that recently aired its eleventh season — all without her. The original Sweet Dee, Reid’s tale sounds like a mixture of breaking up with boyfriend Rob McElhenney at the wrong time and falling prey to classic Hollywood sexism.

“They let me know that while Rob, Glenn [Howerton] and Charlie [Day] had been picked up for the series, I hadn’t been,” she writes. “I got a small payout (the equivalent of one episode’s salary), my agent and manager fired me, Rob married the actress who he hired to replace me … and I never heard from Glenn or Charlie again  — not since the day my relationship came to an end.”

Ultimately, Reid bears Kaitlin “Sweet Dee #2” Olson no ill will and insists that her life has worked out just fine — even if she acknowledges that people likely won’t believe her. “How do I tell a story like this and not sound pathetic?” writes Reid. “How do I say the words ‘I feel good about the decision that I made’ and have anyone in the world believe me, when the other choice would have meant becoming a massively wealthy star of a mega-successful show? I don’t know if it’s possible to convince most people on this point.”

‘Happy Days’

Premiering in 1974, this Garry Marshall-created sitcom about life in the mid-’50s was a huge hit right out of the gate. Which was great news for actor Gavan O’Herlihy, who played Richie and Joanie’s older brother, Chuck Cunningham.

What’s that? You don’t remember Mr. and Mrs. C having an oldest child? That’s because the one-note character (his defining trait was that he always dribbled a basketball) vanished from the show in Season 2, just as it was hitting a stride that would fuel nine more seasons. Years later, the circumstances would coin a term — Chuck Cunningham Syndrome — when Mr. Cunningham gave a touching speech referencing his two children, effectively erasing the character from history.

“I hung around for the first half-season, then asked out of the contract. It wasn’t my cup of tea. It raised some eyebrows, but I’m glad I did,” the actor said in a 2013 interview (another actor, Randolph Roberts, also played the role briefly). In the years since, O’Herlihy built a solid career living in the English countryside and starring in UK shows like “We’ll Meet Again” as well as films like “Superman III” and “Willow,” which reunited him with his former little brother Ron Howard.

‘Friends’

All these years later, it’s hard to imagine anyone other than Matt LeBlanc playing the dim-witted Joey Tribbiani. But the role almost went to Hank Azaria, who auditioned multiple times for the part.

Luckily, this story has a happy ending. Although LeBlanc and his co-stars ended up pulling in $1 million an episode, Azaria’s career blossomed as a go-to supporting star in Hollywood. All those voices on “The Simpsons” paid off nicely, as did roles in hit films like “The Birdcage” and “Along Came Polly” — and eventually, he even got to be on “Friends” as Phoebe’s boyfriend.

‘Spin City’

Much like Hank Azaria, Carla Gugino came thisclose to being the star of a massive sitcom that would run for more than 100 episodes. Much like Azaria, she would eventually make it a footnote by engineering a very successful career. But unlike him, she actually was on the show.

Much like Chuck Cunnigham, Gugino’s Ashley Schaeffer appeared mostly in the first season before being written out of the show in a mutual split. A a journalist, she was meant to romance Michael J. Fox’s character — but it was ultimately decided that the romance just wasn’t working. Now on “Roadies” and starring in movies like “San Andreas,” we think her career has turned out just fine.