Michael Cera and the titular plant might serve as the main selling points of the marketing materials for “Crystal Fairy and the Magical Cactus,” yet the movie hardly belongs to either of them. The best compliment for Cera is that at least his performance does not recall his stock character too much.
Sebastián Silva lets comedienne Gaby Hoffmann run rampant to cause free-spirited mayhem in the piece. And boy, does she capitalize on the chance. She provides basically all the enjoyment the film has to offer.
Hoffmann’s hippy Crystal Fairy joins up with Cera’s Jaime, an American in Chile, to find a magic cactus and harness its hallucinogenic powers. Their quest is not particularly funny, serious, or insightful. It just kind of happens, and then the movie ends, leaving no real lasting impression nor making any strong case for its reason to exist.
The film feels rather ragtag and loose to the point of fault; Silva might have been better off saving thousands of dollars by just shooting the film on an iPhone. Then “Crystal Fairy and the Magical Cactus” would truly have the verité feeling it longs for in prolonged sequences of awkward “naturalistic” dialogue.
Anyone looking for realness and authenticity will just have to find it in Hoffmann, whose Crystal Fairy fearlessly owns the screen. She plays an entire elongated scene in the nude, comfortably and confidently carrying out a conversation while flashing her lady parts to a room full of men. Cera, and everyone else in the film, should have followed her bold lead. C / 
Marshall and the Movies 
Great review. This film was so fucking weird. You pretty much nailed it in your review. I preferred Magic Magic.