PARK CITY — A great film is often one that it transcends the cliches of its genre. The 2015 Sundance Film Festival already debuted one movie that overcame the tropes of the coming-of-age picture, "The Diary of a Teenage Girl," Saturday. And on Sunday, it brought another genre-breaker to the zeitgeist with Alfonso Gomez-Rejon's powerhouse "Me and Earl and the Dying Girl."

Let me start off by saying that the film's main character, Greg (Thomas Mann), would want everyone to know that the dying girl isn't going to die. She's gonna be OK and what you'll eventually see in theaters is really just the story of their friendship. The dying girl is named Rachel, by the way, and she's wonderfully played by Olivia Cooke ("Bates Motel").  

But back to Greg.

Greg has spent most of high school trying to be casual friends with everyone while remaining as invisible as possible at the same time. He avoids the "Gaza Strip" battleground of the school cafeteria by eating lunch in the office of Mr. McCarthy (an almost unrecognizable Jon Bernthal), his history teacher, and spends his time watching foreign language flicks with Earl (a fantastic RJ Cyler). Even though he's known Earl since they were five-years-old he'd want you to know they aren't friends but "co-workers" (Greg appears to have an issue with getting close to people). The two spend most of their free time creating their own skewed versions of classic films such as "Senior Citizen Kane" and "2:48 PM Cowboy."

Life becomes more complicated for Greg when his mom (Connie Britton) forces him — literally forces him — to go befriend his classmate Rachel after she's diagnosed with leukemia. Rachel isn't sure what to make of this, but the two slowly bond even if Greg's inherent awkwardness makes it harder for him than for her. Eventually, Greg gets pushed by Earl and another friend into making a film just for Rachel, but months after starting he can't seem to finish it.

Gomez-Rejon, who is best known for his television work on "Red Band Society," "American Horror Story" and "Glee," displays an unexpected vision in his second big screen effort. He uses stop motion animation, unconventional perspectives (one scene features shots from the POV of a melting popsicle) and self aware titles to frame the story in Greg's voice. And yet, every time the film seems to be slightly inspired by contemporary flicks such as "Submarine" or "Son of Rambo," Gomez-Rejon will introduce an element you wouldn't expect which is nothing like those films. It should be noted, a good deal of the credit for the film's look has to go to cinematographer Chung-hoon Chung, a frequent collaborator of Park Chan-wook.  

Both Gomez-Rejon and writer Jesse Andrews (who adapted his own 2013 novel) seem very aware of how this genre can become predictable and they constantly disrupt the audience's expectations in different ways. They also put a tremendous amount of true-life humor in Greg, Rachel and Earl's friendship at the beginning of the film. That's because Greg probably isn't telling the truth about what happens to the dying girl, but I didn't tell you that, OK?

"Me and Earl" could not succeed, however, without the incredible performances from both Mann and Cooke. This is the best material of their careers and they simply nail it. Outside of the aforementioned Britton, Bernthal and Cyler, Nick Offerman does wonderful Nick Offerman things as Greg's father, Molly Shannon brings some heartbreaking laughs as Rachel's mom and Katherine C. Hughes finds some three-dimensionality for what could have easily been the hot girl movie stereotype.

It's often easy to overhype a film at a festival like Sundance, but "Me and Earl" is as genuinely wonderful as the kudos will suggest. It's a fresh, beautiful and heartbreaking achievement that continues to surprise until the very last scene. It's dangerous to call something an instant classic, but sometimes it's simply the truth.

With over a decade of experience in the movie industry, Ellwood survived working for two major studios and has written for Variety, MSN and the LA Times. A co-founder of HitFix, Ellwood spends his time relaxing hitting 3’s on the basketball court and following his beloved Clippers.