Jerry Ferrara's character on "Entourage," known as Turtle, was first introduced as a pot-smoking slacker living with his movie star friend, working as his chauffeur, and enjoying the perks of being so close to fame.

In the eighth and final season (premiering Sunday at 10:30 p.m. ET/PT on HBO) he's an entrepreneur with dreams of his own success who has Mark Cuban on speed dial.

In real life, Ferrara, now 31, has gone through his own transformation over the course of the show.

He's lost roughly 50 pounds and is looking forward to the challenge of finding work beyond "Entourage."

"Times are a little bit different now. (In the past) if you were a television actor you were a television actor and if you were a movie actor then that's it," he said. "Now people are segueing from TV to movies rather easily and you're seeing a lot of people go from movies to television so I just think there are no rules anymore."

One thing he can add to his resume is writing. After "begging for a few years" for an opportunity, Ferrara co-wrote two episodes of "Entourage" this season after creator Doug Ellin gave him the chance.

"He babysat me along the way," Ferrara said. "It was a goal I had from the very beginning and so we got it in in the last season."

Ferrara says it wasn't easy to write for himself.

"I wanted to write myself out of the episode," he said. "I just didn't want anyone to think I was trying to do this to write myself some cool story-line. ... That was my own neurotic brain thinking."

He says he was "terrified" to get his co-stars' reaction at the table read.

Ferrara is also filming a movie called "Think Like a Man" based on the best-selling relationship advice book written by Steve Harvey.

"My character is the non-committal character. I've been with the same girl for a few years and it's time to go to that next level and it's not happening."

He says he hasn't read Harvey's book but believes "you don't have a best-seller like that if you're just telling lies. He's onto something, which is all I will say."