What everyone knew was that Brooklyn indie-rock breakout Grizzly Bear would provide the overarching soundtrack and score to Derek Cianfrance's "Blue Valentine." What I didn't know was that the film's co-star Ryan Gosling would be providing tunes to the tracklist as well.

The 29-year-old actor plays Dean in this crumbling love story, paired with Cindy (Michelle Williams) whose complaints against her husband include his creative propensity in music and art that he does nothing with. Such talent is evidenced in the film’s sweetest scene: in a flashback to right after the couple just begin to get to know each other, a younger Dean insists Cindy tap dance for him as he plays the ukulele. Declaring that he only knows to sing “goofy” on the song, he fittingly serenades “You Always Hurt the Ones You Love,”  enough to impress his new lady.

Gosling can be seen strumming throughout the Sundance-debuted film, and on a pair originals too. At the Q&A after a screening of the film, he mentioned that he only penned them because the written character called for it – but we know better. Gosling, much like his character, does a nice little job singing, playing and pretending that he doesn't care that he can.

Other oldie-but-goodie tunes took centerstage in the film, including the dissolving couple’s “song,” “You and Me” by Penny and the Quarters and the Platters’ take on “Smoke Gets in Your Eyes.”

Another of the film’s great moments happens in a juxtaposition between Gosling and Williams, when each drives away from a brewing fight with their own specific soundtrack: Dean with The Dirtbombs and Cindy with Pat Benetar.

Grizzly Bear songs “Easier,” “Dory,” “Foreground,” “Granny Diner,” “Lullaby,” “I Live With You,” “Alligator (Choir Version)” and “Shift (Alternate Version),” none of which are previously unreleased, are all included in the final cut of the film shown at Sundance. Department of Eagles, side project of Grizzly’s Daniel Rossen, also contributed “In Ear Park.”

Songwriting and strumming notable Matt Sweeney (Guided by Voices, Johnny Cash, Bonnie “Prince” Billy) rounded out “Blue Valentine’s” score with additional, chilly guitar lines, and collaborated with one-third of Peter Bjorn & John (Bjorn Yttling) on a track called “North Haven.”

Read HitFix critic Greg Ellwood's complete review of this realistic, intense and "superb" film.