Last year, filmmaker Sebastian Silva and arbiter of awkwardness Michael Cera traveled to remote Chile to make a movie. It featured keen character psychology, a knack for dramatic tension, and the troubling adventures of a displaced American woman. The film, a psychological thriller, was called Magic Magic. In the film, Alicia (Juno Temple) goes to visit her cousin in the Chilean countryside. While surrounded by a group of relative strangers (including an uncharacteristically creepy Michael Cera), Temple’s character begins spiraling into insomnia and paranoia.

But Magic Magic wasn’t the only film that Silva and Cera made while sequestered in Chile. While waiting for the film to be financed, the pair worked on another project, the considerably more cheerful Crystal Fairy & The Magical Cactus, a drug-fueled road trip comedy. While Magic Magic was the larger production and boasted an impressive cast, it was ultimately Silva’s looser and more improvisational film that won over audiences at Sundance where both films premiered, winning him the Directing Award for World Cinema. Despite the two films’ ostensibly disparate subject matter, Silva’s trademarks ring true just as strongly in Crystal Fairy as in Magic Magic. A focus on character psychology prevails; moments of dramatic tension peek out of the lighthearted premise; and perhaps most importantly, Crystal Fairy is invested in the complex nature and emotional journey of its title character, an American free spirit played by a magnetic Gaby Hoffman.

Before we meet Crystal, we are introduced to the film’s other star. Jamie (Michael Cera) is a boorish American expat living with his friend Champa (Juan Andres Silva) in Chile. Jamie is selfish, pushy, and focused on finding the perfect high—characteristics that become evident in the film’s opening moments. Between lines of coke at a party, Jamie meets a dancing hippie named Crystal Fairy and drunkenly invites her on his and Champa’s quest for an elusive hallucinogenic, the San Pedro cactus. The next morning, Crystal is more than ready to join the trip (on the road and otherwise), much to the sober Jamie’s chagrin. The plot unfolds like any good road trip movie. The trippers encounter a series of challenges and delays en route to pursuing their magical cactus.  Crystal’s role as earth-mother-shaman is continuously pitted against Jamie’s unrelenting selfishness, fueled by his growing monomania to find a cactus.

It is the energy of these clashing characters that gives life to a heavily improvised script, one that tends to meander and feel scattered at times. Silva’s ability to subtly shift our opinions of the pair over time is particularly effective. At first, Crystal is a pain in the ass. She chastises the guys for their choice of junk food; she insists on putting “magical pebbles” in their drinks; and she unabashedly walks around their hotel room in the nude. (A large kudos is deserved to Hoffman for her staunch nudity—all natural nudity, it should be added; the boys nickname her “Crystal Hairy”). During these unrelenting earth mother antics, we even begin to side with Jamie. But Crystal’s flagrant strangeness is only rivaled by Jamie’s capacity to be a huge asshole. Soon the tide begins to shift. Crystal’s kindness and genuine consideration surface just as Jamie’s impatience and mean-spiritedness begin to boil over. The group’s preference—and, in turn, the audience’s—begins to tilt clearly in Crystal’s favor.

This shift is precipitated in part by Gaby Hoffman’s captivating performance. Hoffman succeeds at packing an emotional punch into a character who could have been cast aside as frivolous or overtly comedic if placed in the hands of a weaker performance. Or, god forbid, the role could have tread on manic pixie dream girl territory. Instead, Hoffman pairs Crystal’s flying freak flag with an honest vulnerability. Her crazed antics segue fluidly into revealing a character who turns out to be more emotionally damaged than we ever could have thought.

Cera is equally impressive as Jamie, capturing the character’s anti-heroism to a T. The move away from his usual roles as a bumbling nice guy is a refreshing one for Cera. The other performances, delivered by Champa’s brothers (and played by the real-life Silva brothers) are lackluster in comparison to those of Hoffman and Cera. However, they primarily serve to function as reactions to the behavior of Jamie and Crystal, and in that regard, they are entirely effective.

With the help of stellar performances and the beautiful Atacama Desert as a backdrop, Silva’s film is in many ways the ideal summer road trip movie. It doesn’t try to be overtly funny or sappy. Rather, Crystal Fairy is a film about the challenge of interactions. Although Jamie claims he is excited to be sharing in the group experience, he spends the majority of the film isolating himself. Crystal embraces the world, but is more deeply troubled than she appears to be. The trip ultimately leads Jamie and Crystal to reevaluate their identities in a much more emotionally resonant way than most drug-fueled romps would. The climax of the trip ends not in a bout of drug-induced hilarity, but rather in a surprising moment of emotional catharsis and introspection.