Based on his namesake 2011 graphic novel, Kid Koala’s directorial debut, Space Cadet, is not your typical animated sci-fi kids flick. The story of a young astronaut named Celeste and the sad robot assistant she leaves behind on Earth, Space Cadet is less an intergalactic adventure than a poignant portrait of friendship and loneliness—and it’s told entirely without dialogue. Accordingly, its soundtrack is teeming with melancholic piano sketches (“Birthday”) and oscillating neoclassical experiments (“Luminel System”) that set the film’s meditative tone and strike the necessary emotional chords. But a more whimsical spirit emerges through playful old-timey serenades (“Paper Doll,” featuring Nova Scotian singer-songwriter Meaghan Smith) and loopy lo-fi rap tracks (like “Rise,” featuring feisty guest verses from Digable Planets star Ladybug Mecca) that nod to the Kid’s turntablist roots.