Here’s what you need to know. Director Justin Lin and his co-producer/star Vin Diesel know why we’re here; we want to see some crazy action scenes with characters we know so well that when Dom says once again that he doesn’t have friends; he has family, we almost feel that we’re part of the family now, too. So, “F9” delivers what the fans want, which is more and wilder action, and a bit more family, too. In fact, this time we get some backstory, with teenage brother and sister Dom (Diesel) and Mia (Jordana Brewster) and their dad, race car driver Jack Toretto (JD Pardo). It turns out there’s another brother, too, Jakob (Finn Cole). And we get to see how a tragedy on the racecourse leads to the brothers going in different directions. Jakob comes back into the story as John Cena.

If you’re a casual fan, all you need to know is that this movie has a lot of fun, if highly improbable, action scenes, including Vin Diesel as a passenger in a crazy car chase through London with none other than Dame Helen Mirren at the wheel. If you’re really into the series, you’ll want to know that many other favorite characters return, some more surprisingly than others. Also, if you’re really into the series you already know that the third movie in the series is the eighth in the chronology (also the first directed by Lin). That movie ended with another tragic exploding car death, of a mentor named Han (Sung Kang). But if we’ve learned one thing from this series, it is that sometimes people you think were either dead or bad turn out to be neither.

Two scenes I particularly loved will be the best litmus test for your decision on whether to buy a ticket (and if you do, please make it the Dolby experience). We’ve all seen fights before. We’ve seen fights where our two guys take on six bad guys. We’ve probably seen fights in the back of a big moving van, but here’s where the “Fast and Furious” franchise says to themselves, “How can we make things even more interesting?” And at some point someone says, “Let’s have the fight take place when the van is being (a) being chased by more bad guys, (b) being driven by someone who has never driven before, and (c) carrying the world’s most powerful electro-magnet, which is being turned on and off, sometimes on purpose and sometimes not. Wow.

The other scene has Roman, the comic relief character played by the almost-impossibly handsome Tyrese, says something that does not quite break the fourth wall between the characters and the audience but bends it a little. He mentions the un-mentionable — somehow no matter how many of the most lethal weapons ever conceived are shooting and exploding all around them, no matter how outnumbered they are, no matter how many impossible jumps they attempt to make in vehicles, somehow they all walk away without a scratch. Could it be, he wonders, that they’re not human? The real-life answer is that they’re not; they’re fictional characters. His conjecture is, maybe, that they could be un-killable? The real-life answer to that one is yes, as long as people keep buying tickets to the sequels.

In another scene, a character says, “If this was a movie, this would be when….” just to remind us that they know we know.

They can’t make the title any shorter. What’s the next one going to be called, just F? Will there be another “Hobbs & Shaw?” A spin-off about Dom’s early days? If they feature Helen Mirren and a Pontiac Fiero shot into space or whatever even crazier stuff they can dream up, I’m in.

NOTE: Stay for the mid-credits sequence for another familiar face.

Parents should know that this film includes constant action and peril including teenagers witnessing the death of a parent in a fiery crash and endless shoot-outs and chases, one through a minefield. Characters use strong language and drink beer. Bad guys plot world domination.

Family discussion: When does someone deserve a second chance? Should Letty have called Mia?

If you like this, try: the other films in the series, especially “Tokyo Drift” and “Hobbs & Shaw.”