Dope is fun. Dope is energetic. Dope is ambitious. But Dope is also confused. Dope is messy. Dope is disappointing.

Dope kicks off as a fun coming of age comedy.Straight A student Malcolm (a terrific turn from newcomer Moore), with his hair sculptured like House Party’s Kid, likes nothing more than riding his BMX, playing Gambeoy, listening to his Walkman, and cruising record stores for 2 Live Crew and EPMD albums with Diggy (Clemons) and Jib (Revolori, The Grand Budapest Hotel). But when a conversation turns to Bitcoin we realise we’ve been had: this isn’t the early nineties - these three geeks are committed retro freaks.

The retro fun is then sidelined when Dope morphs into a stoner comedy á la Pineapple Express (a stoner comedy where everyone stays sober). Following crush Nakia (Zoe Kravitz) into a club, a shootout and a mix up ends with Malcolm accidently going home with a lot of MDMA in his schoolbag. He’s contacted by the irate owner to hand over the drugs but is warned by his local ‘friendly’ drug dealer Dom (Rocky) that he’s either meeting a killer or a snitch. Malcolm and his buddies run.

A few mini scrapes and adventures later, Dope moves into gross out sex comedy territory for twenty minutes before it changes tack again when the gang decide to package and sell the MDMA through dodgy websites with the help of hacker/stoner Will (Blake Anderson). By this stage the romance with Nakia and Malcolm’s Harvard interview are long forgotten. It then swings once more (into a message on racial perception and masculinity) and we’re rubbing up against the end credits.

It’s all a bit random. A shootout is followed by a quiet romantic scene, a tense drug deal is followed by a fun recording session (oh yeah, the guys have a band too). There’s no consistency, no follow through, and proceedings can stop at any moment for a debate (who can say n****r and why) or for a fart about on YouTube (a montage of people on their drug).

But the Moore/Clemons/Revolori chemistry gets it over the line and Famuyiwa’s challenging of the perception of the black teen in film, while a little on the nose, is fresh: Malcolm is from a tough neighbourhood (The Bottoms, Inglewood) but he’s a virgin, never held a gun, hasn’t done drugs, and has ambitions for Harvard – not everyone is Menace II Society, Famuyiwa is at pains to point out. But it’s when the director isn’t trying so hard that Dope shines: one scene has Malcolm and Nakia yap about prom prospects – and you realise that this scene is hardly ever played by black teens.

Oh, and the soundtrack is pumping. Obviously.