The pic, shot in London by Argentine director Alexis Dos Santos, kicks off the fest's competition of 14 European films, all of which are directorial debuts or second pic.
Most contenders have already visited major festivals, some collecting kudos on the way. Peter Strickland's "Katalin Varga" came away from Berlin with a Silver Bear, while Mahmut Fazil Coskun bagged a Tiger at Rotterdam with "Wrong Rosary."
Less familiar are "La Casa Sulle Nuvole" from Italy's Claudio Giovannesi, "In Your Veins" from Sweden's Beata Gardeler and "La Verguenza" from Spain's David Planell.
Belgian no-budget drama "Somewhere Between Here and Now" by Olivier Boonjing also makes its bow in competition.
Previously strict about only including debut and sophomore features, Brussels has expanded its horizons with a program of contenders from the European Parliament's Lux prize for European cinema.
Four of the 10 films on the long-list will screen: "35 Rhums" by Claire Denis, "North" by Rune Denstadt Langlo, "Welcome" by Philippe Lioret and "Katalin Varga."
Short list of three will be announced at the Venice Film Festival.
Brussels closes July 5 with non-competing French comedy "Bancs Publics," helmed by Bruno Podalydes.