All hail Ridley Scott! The director behind "Blade Runner" and "Alien" has saved us from the cinema doldrums, bringing to theaters the first must-see film of the fall, "The Martian."

Matt Damon stars as NASA botanist Mark Watney, who's presumed dead and left behind while on a mission on Mars. There, 500 million miles away from Earth, he must discover a way to survive until a rescue mission can be mounted. And that could take years.

It's "Castaway" on Mars, and it's absolutely marvelous. Scott maintains a delicate balance between science speak and accessible explanations so any viewer can keep up with Watney's methods, and NASA's eventual efforts to save him. Beyond that, this master filmmaker also manages to infuse his intensely realistic sci-fi adventure with a thread of macabre humor that makes "The Martian" a sophisticated delight. Watney often laughs in the face of death, because, really, what other choice does he have? And Damon is pitch-perfect in capturing the astronaut's weary resilience, wry humor, amiable cockiness and defiant never-say-die attitude. (Bonus: Its message about the importance of a positive attitude makes it the movie "Tomorrowland" dreamed of being.)

Where "Castaway" had its Wilson volleyball as an outlet for its hero to share his inner thoughts and feelings, "The Martian" has a system of video journals through which Watney shares his frustrations, failings and victories. With a glint in his eye and that signature crooked smile, Damon sells this direct-address device beautifully -- aided by Drew Goddard's warm and wickedly smart adapted script -- making dialogue like "I'm going to have to science the shit out of this" into winsome laugh lines. That's not to say "The Martian" is a comedy; these laughs are more a valve to relieve the insane suspense Scott builds over the course of Watney's journey.

In its first few minutes, the film speeds into its inciting incident: In the blink of an eye, a barely introduced Watney is gone, and his crew mates (Jessica Chastain, Kate Mara, Sebastian Stan, Aksel Hennie and "Ant-Man" scene-stealer Michael Peña) must make the traumatizing decision to leave without him. From there, Watney must not only come to grips with the most dire situation any astronaut has ever faced, but also mend his own gory abdominal wound in a scene that is "Prometheus"-level in its gut-wrenching body horror. (Who needs evil alien space babies when you've got Damon sweating bullets as he burrows into his side to scrape out shrapnel?)

Each of Watney's missions (building a garden, scouring for equipment, repairing his damaged body) is a finely tuned action scene, as cut by Pietro Scalia ("Gladiator"). The audience is riveted because "The Martian" makes it clear that every move matters, and every mistake could mean Watney's death. This tightly wound tension will not only put you on the edge of your seat, but also will turn your stomach as it builds to the movie's eye-popping finale that delivers the kind of iconic special effects and stunt work that we've come to expect from Scott.

The gravity of Watney's isolation is underlined by impeccable cinematography of Dariusz Wolski ("The Counselor," "Prometheus," "Exodus: Gods and Kings"), which revels in the expanse of the theater screen the way "Lawrence of Arabia" did in 1962. In these grand, desolate red deserts and rock formations, there's nothing but Watney and his determination to live. It's an awe-striking visual enhanced by 3D, adding profound dramatic weight to this sensational cinematic experience.

But unlike "Castaway," the film isn't shouldered solely by its lost protagonist. "The Martian" boasts an outstanding ensemble that also includes Chiwetel Ejiofor, Sean Bean, Jeff Daniels, Kristen Wiig, Benedict Wong, Donald Glover and Mackenzie Davis. All of them crush it. Chastain delivers another hard-as-nails heroine. With a subtle but sweet turn, Mara makes us forgive her for "Fantastic Four." Peña and Glover bring in scads of charm and some loonier (and welcomed) humor. Ejiofor is thrilling as the face of the rescue effort on Earth, earnest but plagued by doubt.

The cast is diverse in a way that feels authentic (which suggests Scott learned from the criticisms of his white-washed biblical epic "Exodus: Gods and Kings"). More importantly, together they've created the next great American movie. It's an accomplishment the film itself seems to recognize with a victory-lap end-credit sequence that gives all of the above their own resolution moments and title cards.

Beyond being breathtaking in its visuals, action, tension and performance, "The Martian" is exhilarating in its portrayal of humanity. You see people of every shape, size, color, creed and gender pulling together to save the man on Mars. It's an exaltation of humanity and human endeavor that will make you want to stand up and cheer. It's a celebration of science and all things nerdy (look out for clever cutaways to Sebastian Stan and Sean Bean respectively when "Iron Man" and "The Lord of the Rings" are mentioned.) And it's fueled by a disco-heavy soundtrack that is oddly perfect. (If you don't laugh as the final song sounds over the credits, you may be dead inside.)

Simply put: "The Martian" is a great movie on every level -- and it may just be the best film of 2015.

"The Martian" opens Oct. 2.