Time travel is usually just a good way to riddle a film with plot holes. For evidence see any movie in the Back to the Future trilogy, which is perfect despite its flaws. No matter how intelligent the script may be or how thoroughly its theory of time and time travel is fleshed out, paradoxes are inevitable. Strangely enough, the third installment of the Men in Black series handles the oft-used sci-fi motif brilliantly by keeping its view of the time line as vague as possible.

In Men in Black 3, agents K (Tommy Lee Jones) and his partner J (Will Smith) are back again to save the world from an alien threat. This time it comes in the form of Boris the Animal, played by a nearly unrecognizable (much to the makeup artists’ credit) Jemaine Clement of Flight of the Conchords fame. Boris is the nastiest creep in the galaxy, and also one of the most dangerous. K imprisoned him on the moon, saving Earth from imminent destruction 40 years ago, and for all that time, Boris has been planning his revenge. He escapes and tracks down a device to send him back in time so he can dispose of K and lead an army of super villains in an invasion of Earth. Boris succeeds–sort of.

The Animal’s plan did not take J into account. J finds himself in a present where K had perished at Boris’ hands; however, J’s the only one who seems to remember the reality where K was triumphant. It’s up to J to travel back in time and set things right. In 1969 New York City, he runs into K as a younger man (played by Josh Brolin) and the two team up to combat the duo of Borises.

It’s hard to believe that the first Men in Black movie was released almost 15 years ago. (It’s been 10 since the release of the sequel.) Then, the Barry Sonnenfeld-helmed mega–blockbuster was a technological marvel. Now, with Sonnenfeld back in the director’s chair for the third time, Men in Black isn’t much different from any other computer effects-riddled sci-fi/action flick. What does separate it from the rest of the schlock out there is its creativity. The creatures, such as a giant extra-terrestrial fish encountered in the back of a Chinese restaurant or even the grotesque character of Boris himself, are bursting with personality.

Another thing it has that other franchises lack is its star, Smith, as viable a big budget actor as there is. MiB 3 is something of a comeback for the Fresh Prince; it’s been three years since his performance in the somewhat dour Seven Pounds. Here, he’s the charming, wise-cracking, yet still believable action hero we’ve all come to know and love. No doubt he has a great team around him–as if the aforementioned costars weren’t enough, Emma Thompson also chips in as agency head O–but this is the Smith show, and he pulls it off with such casual ease that it hardly seems like he’s accumulated any rust in his time away from the silver screen.

However, as it turns out, the problematic plot device of time travel actually happens to be the film’s greatest boon. Not only does it allow for another nifty performance from Brolin, but it also opens the door for some surface discussions on the nature of time and probability. The character of Griffin (Michael Stuhlberg), who much of the film’s conflict hinges upon, is of a race of beings who exist in “the fifth dimension.” Griffin has the ability to see infinite possibilities and multiple outcomes. It’s sort of a beginner’s guide to string theory and leads to some of MiB 3’s more interesting and even thought-provoking moments. Stuhlberg’s performance is sweet and comical, forging an endearing character.

Of the utmost importance, The Men in Black series is about entertainment, and while this film, like those that proceed it, may not be groundbreaking, innovative or all that memorable, it does well not to take itself too seriously. The mood is light, even when a creature that lives in Boris’ hand is shooting spikes through people’s foreheads. Hey, it’s all in good fun. Who knows if this will be the last time Jones and Smith down the black suits and sunglasses, but if it is, they’re certainly going out in style.