You’re probably expecting me to talk about the cast of Source Code at some point in this review. After all, it does have a very good set of actors. Jake Gyllenhaal is the name above the title, and he’s shown a ton of charisma in his past roles. Furthermore, he shares the screen with such under-rated talents as Michelle Monaghan, Vera Farmiga and Jeffrey Wright. But I’m not going to talk about the cast. Not just yet. Because first and foremost, the true star of this film is Duncan Jones.

The son of David Bowie hisownself, Jones made his film debut two years ago with a woefully under-seen film titled Moon. If you value your movie-loving credentials, you’ll track that film down immediately and see it if you haven’t done so already. Using little more than a single actor and a budget smaller than that of a Super Bowl commercial, Jones managed to make a gripping and immersive work of science fiction beauty, doing so on only his first try. Movie fans all around the world saw this and waited with eager anticipation to see Jones’ next and learn more about him as a film-maker.

Though Source Code was clearly made with a bigger budget, it still carries over a lot of what made Moon such a wonderful film. Both movies managed to tell a story that’s epic in scope, but with strictly confined settings. Both movies are visually dazzling and set to wonderful music (even if it’s Chris Bacon doing the score instead of Clint Mansell). Both films have complex and high-concept science fiction premises that deal heavily in such themes as survival in isolation, conflict with authority, the subjective nature of reality, mortality, identity, the value of life, the ethics of using human beings as expendable tools toward a greater good and a myriad of other issues relating to the human condition.

However, Jones’ first film had something that his second film didn’t: A premise with some slight measure of credibility. Therein lies the rub.

I’m not going to try describing the premise for Source Code because 1) just as with Moon, you’re better off going into this film knowing as little as possible, and 2) the trailer does a better job describing the intricacies and complexities of the premise than I ever could without getting into spoilers.

You may be wondering how this premise could be made plausible in any way. You may be wondering why our hero Colter Stevens (Gyllenhaal) takes over the same body every time. You may be wondering how he could possibly affect reality while in a computer program. Don’t. I can’t tell you how Jones establishes the premise so it makes scientific sense, because he doesn’t. Suspension of disbelief in this film is as critical as it is difficult. That’s the bad news.

The good news is that even if Jones doesn’t make suspending disbelief easy, he at least makes it comfortable. There are a lot of difficult concepts to comprehend in this film, but they’re all nicely spaced out and presented in an order that’s easy to follow. This film takes its time with the story points, giving us some breathing room to take them in and digest them, yet Colter is so repeatedly thrown into the fire and with such indifferent violence that the film never seems like it’s lagging. Furthermore, the camerawork and editing do a phenomenal job of clarifying and elaborating the premise while also varying in ways that keep the repeating eight minutes from getting dull. Furthermore, even if the logic behind them is non-existent, at least the rules are kept consistent and used in interesting ways. That is, until the ending.

The ending for this film is a cheat. Plain and simple. For one thing, it utilizes pseudo-quantum physics when the rest of the premise seemed to hinge on pseud0-neuroscience. Secondly, it opens up quite a few plot holes as to just what consequences the Source Code really has. In every possible way, this ending shouldn’t work… and yet somehow, it does. The ending gave me a warm fuzzy feeling, mostly because the characters worked so damn hard to attain it and the filmmakers worked so damn hard to sell it. In the service of theme and narrative, for better or for worse, this film could not have ended any other way.

As for the cast, they all do serviceably. Gyllenhaal is clearly enjoying this chance to sink his teeth into some meatier material and he has enough charisma to make the character work, even if his character’s whining (while understandable) did get a touch annoying at times. Monaghan’s character is totally unmemorable, mostly because she’s given nothing to do aside from being adorable and freaking out when “Sean” does something crazy and/or stupid. She’s more of a character motivation than an actual character, but Monaghan is beautiful and charming enough to make it work.

Jeffrey Wright does very nicely as the Source Code’s inventor, a brilliant man who’s very matter-of-fact, yet also very arrogant and kind of a douche. Imagine a guy who’s tired of always being the smartest person in the room and you’d be getting close. By far the best in this film’s cast is Vera Farmiga, who plays Colter’s immediate supervisor. Farmiga delivers a woman who’s clearly sympathetic to everything that Colter is going through, yet she’s struggling against the military protocols that inhibit her ability to help him. And anyway, she’s far more concerned about all the millions of innocent people who could die at any moment if Colter doesn’t stay focused and complete the mission. Can you blame her?

Ultimately, watching Source Code is like making a bargain with Duncan Jones: He’ll show you a creative and exciting film, loaded with great philosophical ideas and a ton of heart… but only if you don’t ask any questions about the underlying premise. This is the rare film in which “turning your brain off” will actually lead to an intellectually nourishing experience. Such a level of suspending disbelief will be impossible for some people, and they’d do well to avoid this film. All others are in for a real treat.