“Do whatever it takes. It’s that simple. You can’t fail if you don’t give up.”

Words of wisdom expressed with genuine feeling from a husband and a father to a young man trying to find a way to fix the crises gripping his life. Too bad Michael (Zach Braff) doesn’t get a chance to hear them until after he’s virtually destroyed his three-year relationship with pregnant girlfriend Jenna (Jacinda Barrett). He’s worried that, just months before his thirtieth birthday, there are no surprises left for him in his life, the thought of that being true enough to drive Michael mad.

It also happens to be enough to shuttle him into clandestine conversations with sexily flirtatious coed Kim (Rachel Bilson). She’s a total trip, the fun and friendly music major (“I’m a flutist,” she declares winsomely with a wink) a reminder of the life the successful young architect used to lead before discussions of mortgages and marriage entered his nightly dialogues.

Making it worse is the fact his friends’ love lives are all a complete mess. Best bud Chris (Casey Affleck) is on the verge of seeing his own marriage fall to pieces, while the neurotic and unfocused Izzy (Michael Weston) is still obsessing over a girlfriend who dumped him yet couldn’t supply a reason for doing so. Heck, even the elders are experiencing romantic travails, Kim’s parents Anna (Blythe Danner) and Stephen (Tom Wilkinson) on the path to separation after over thirty years of supposed marital bliss.

Based on the acclaimed Italian production “L’Ultimo Bacio,” Tony Goldwyn’s “The Last Kiss” is the first great film of the young Fall season. Featuring an astonishingly complex and multilayered screenplay by “Crash” and “Million Dollar Baby” Oscar-winner Paul Haggis, this movie is a minor revelation. It’s not just about young adults venturing into the uncertain wilds of their 30’s, it’s also about how relationships dearest to us change and evolve with the passage of time. It is a highly perceptive drama with no good guys and no bad guys, instead choosing to fill its running time with real people facing real issues, all of them searching desperately for the best road leading to solace in their ever-complicated lives.

By and large, this movie is absolutely wonderful. While the main thread belongs to Braff and Barrett, “The Last Kiss” is an ensemble effort where almost every cast member gets an opportunity to shine. In fact, the subplot concerning Anna and Stephen nearly brought me to tears, the luminous Danner so brilliant she took my breath away. Wilkinson nearly matches her (a late sequence between him and Braff a total knockout) but it is her performance I couldn’t shake afterwards. The actress bewitched me, Danner’s emotional complexity so stirring her performance is darn near Oscar-worthy.

Of the rest of the tangents, some work better than others. I loved Affleck in this, two of his moments (one with his wife and child, the other facing down Barrett while holding information he didn’t want any part in possessing) so sublime they startle in the effectiveness. Unfortunately, I can’t say the same for either Weston or Eric Christian Olsen (playing Michael’s promiscuous bartender friend Kenny). Their storylines aren’t fleshed out or interesting enough to make an impact, the former’s too inert and uncomfortable to illicit Izzy any sympathy.

It doesn’t help that Haggis’ script, while excellent overall, does tend to leave a few of the female characters out in the cold. Both Chris’ wife and Izzy’s girlfriend are shrill and uninteresting, nothing more than generic stereotypes giving their men easy excuses to ponder going down the paths they eventually choose. Bilson also finds herself a tad bit stranded, Kim a strangely beguiling enigma who isn’t so much a real person as she is a catalyst allowing Michael an opportunity to potentially stray. That the character remains intriguing is due completely to the actress, the popular “The O.C.” hottie showing depth and maturity as an actress I’d never imagined she possessed.

Thankfully, the rest of “The Last Kiss” borders on the remarkable. Braff and Barrett are both wonderful, each taking their characters to poignant chasms absorbing and true. The choices they make are maddening, affecting, distressing and sincere, each move ones I could, almost hauntingly, imaging contemplating or making in my own everyday life.

In the end, this is what gives the movie its visceral power. None of us like to believe we’re going to make choices putting our relationships in jeopardy even when the reality facing us square in the face is usually quite different. Michael’s decisions are sometimes deplorable, so much so they risk making us lose our affections for the guy. But they are also understandable, and as such the drama they end up producing becomes that much more emotionally spellbinding.

Goldwyn rebounds nicely from the disastrous “Someone Like You” reminding us all about his confident and subtle direction of the 1999 Diane Lane winner “A Walk on the Moon.” The filmmaker lets his scenes build slowly and with a calm eloquence, guiding the actors to cover the peaks and valleys inherent in their characters at their own seductively intoxicating pace. Better, he and Haggis don’t offer any simple solutions to the romantic pitfalls facing their creations, instead ending things on a hopeful-yet-mysterious coda which stays true to the dramatic tonality of the rest of the piece.

I liked this movie. It does not get any simpler than that. The cast is uniformly excellent while Haggis’ script and Goldwyn’s direction border on the masterful. But the reasons this one works so well go beyond the obvious. The movie sticks with you like great cinema should, its nuances as fascinating after you leave the theater as they were while you are sitting in your seat letting them wash over you making “The Last Kiss” a peck on the cheek impossible to resist.