With F9, John Cena joins the Fast & Furious franchise as Jakob Toretto, brother of series lead Dominic. But an additional sibling for the grim, noble outlaw -- his sister Mia is the only one previously mentioned in the series -- is confounding for fans who wonder where Jakob has been and why he has never been seen.

F9 director Justin Lin, who also directed franchise entries The Fast and the Furious: Tokyo Drift, Fast & FuriousFast Five and Fast & Furious 6, acknowledged the conundrum in an interview with Entertainment Weekly. Especially since Dom, as the leader of the crew, often speaks of family as the most important thing. But according to Lin, "Everything's going to be accounted for."

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Fast & Furious, the fourth movie in the series, makes a passing reference to the Torretto family tree when Mia and Dom have a conversation before Dom goes off for revenge. Mia says to Dom, "How do you say goodbye to your only brother?"

"We're going to earn that line, I promise you," Lin said.

Vin Diesel, who stars as Dom, was impressed with Lin's idea of how to integrate Jakob into the mix. "It was a very interesting concept. Even the person that is the spokesman for brotherhood could have a broken brotherhood in the past," Diesel said.

Directed by Justin Lin, F9 stars Vin Diesel, Michelle Rodriguez, Tyrese Gibson, Chris "Ludacris" Bridges, John Cena, Nathalie Emmanuel, Jordana Brewster, Sung Kang, Helen Mirren, Kurt Russell and Charlize Theron. The film arrives in theaters June 25.

KEEP READING: John Cena Explains Exactly Why the Fast & Furious Franchise Works

Source: Entertainment Weekly