'Fast 9' director Justin Lin was only going to return for one 'Fast and Furious' sequel until Vin Diesel pulled him aside to convince him to stay and oversee the final trilogy

• "Fast and Furious" director Justin Lin planned to leave the saga after making 2013's "Fast 6."
• Lin told Insider the idea of exploring Dom's origin story drew him back in.
• Once he agreed to do "F9," Lin said star Vin Diesel convinced him to stay for the final trilogy.

"Fast 9" director Justin Lin really didn't plan on coming back to the "Fast" franchise after 2013's "Fast 6."

"I really did mean it when I left," Lin recently told Insider over Zoom while discussing "F9." "Han [played by Sung Kang] and I left. We were not coming back. The studio has always been really gracious in always checking in to see how I was feeling. I, very much, I didn't want to come back unless it was for the right reason."

Lin previously directed four films in the franchise (three through six). Even after he left the "Fast Saga," Lin and Diesel kept in touch over the years and the actor would always end up talking about Dom.

"I thought, it was cool. We could talk about Dom, but I'm out," Lin said.

What brought him back to do not one, but three more films in the franchise?

Family.

"It wasn't until the idea of further exploring this theme of family, but through blood that excited me because I knew that if we were going to do that, there was a really great chance that we were going to be able to kind of go back and explore and solidify some of the origins of this mythology," Lin said.

"Fast 9" introduces Dominic Toretto's younger brother, Jakob (John Cena), for the first time in the franchise. Part of the mystery in the ninth film is how we've never heard of the younger Toretto until now, given that family is at the core of Dom's code.

Lin told Insider the inspiration for Jakob's introduction came from something that was happening to him in his personal life. The director didn't expand on that, but added it wasn't one of the hardest elements of the film to nail down.

"Because it's personal, I think it kind of found itself very, very, very quickly," Lin said.

Lin said once he agreed to do "F9," Diesel wouldn't let him go.

"Once I kind of agreed, Vin kind of pulled me aside and he said, 'You're not leaving,'" Lin said, laughing. "We're finishing this thing up."

"I've always felt like when we do these movies, especially when we started, a sequel was not a given. If we were able to earn one, let me think of it as one at a time," he added, saying that's not the approach they took for the next three films.

Lin said he and Diesel have been discussing the final chapter of the franchise "for the last nine or so years."

For fans, it's probably comforting to hear that Lin and Diesel have been mapping out the final trilogy of the now $6 billion Fast Saga for a long time. We've seen what happens when you don't have a trilogy plan in place for a billion-dollar movie franchise like "Star Wars."

Currently, there are two final chapters still to come in the main "Fast and Furious" saga.