WARNING: The following contains spoilers for F9, now in theaters.

In the Fast & Furious series, Vin Diesel's Dominic Toretto is considered the engine of the franchise, stringing everyone together, doing a lot of heavy-lifting and rallying the troops to build an unshakeable movement. It's why most movies revolve around him turning his criminal life around and later becoming a super-spy. However, as F9 proves, the true heart of the family isn't actually Dom -- it's his soulmate and wife, Letty Ortiz (Michelle Rodriguez).

Letty's been a Day One, proving to be an integral cog in the first movie and since then, she's embodied the sense of heart most. From her defending Vince and Dom's other friends when they got sketchy, to her keeping Dom in check, to her even being cynical about Paul Walker's Brian, she's been the eyes and ears for their entire crew.

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It's vastly overlooked, as the focus is on Dom as the muscle, but while he's the brawn, Letty has subtly been the brain. Without her as the glue, the team would fall apart, which is why when she was presumed dead, Dom lost himself. As a result, when it turned out she was alive, he fought tooth and nail to get her back and restore her memories. It might have been seen as forced romance and drama, but he knew Letty was the one who made the racers tick.

F9 really brings this home when Roman and co. reveal Mr. Nobody has gone MIA and Cipher's been taken. They're eager to finish the job and get her back for the government, but Dom wants no part of it. He doesn't care if Cipher killed Elena, mother of Little Brian; he thinks fatherhood should keep him out the game. But Letty doesn't buy into that, reminding him of honor.

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And no matter what, Letty considers Elena family because apart from her helping Team Toretto out as a government agent, she doesn't see Elena's hiding the truth about Dom's son being born as a betrayal. Letty understands the pain Elena went through after she and Dom got back together, and it's why she wants to avenge Elena and get rid of Cipher. That says a lot, and the way Letty looks after Brian as if he were her own espouses everything Dom spoke of in the past when it comes to unity and love.

And so, Letty joins the mission, inspiring Dom to not be a hypocrite and pull up late. On top of that, when they discover Jakob's involved, Letty's the one who tells Mia about it behind Dom's back because she believes the sister should know that their little brother has gone rogue. But also, Letty can see that Mia may be the key to pulling Jakob away from the darkness. That notion never crosses Dom's mind, as he's selfishly wrapped up in his bitterness.

The icing on the cake comes with Letty then using Mia to piece another puzzle together, leading them to Han, who ultimately has the details on the weapon, Ares, and its key. Clearly, without Letty, their war on terrorism in F9 just can't happen, and it all stems from her being a strong, independent woman who thinks like a sister, a mother and most of all, a real leader.

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 is in theaters now.

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