Here’s an underdog sports comedy from the US that is also a pop culture in-joke. It’s a feature-length version of a series of basketball-themed TV ads for Pepsi Max that star a jokey oldster character called Uncle Drew (played in elaborate prosthetic makeup by real-life NBA star Kyrie Irving). He is an ageing street basketball champ and a cantankerous veteran of the 1960s who doesn’t approve of “rappity hippity-hoppity” music.

This comedy features a young team manager called Dax, played by comic Lil Rel Howery – now well known for playing the hero’s friend in Get Out, a film which this film shamelessly references, just for those people who don’t get this actor’s pedigree and added star value. Dax’s key player lets him down by going over to an obnoxious rival, so poor Dax needs to assemble a new squad to compete in Harlem’s longstanding Rucker Park street basketball championship. Someone tells him about the legendary Uncle Drew, and Dax persuades this crotchety icon to help, and also to sign up his equally brilliant but geriatric comrades to make up a new scratch team.

There are loads of cameos from genuine basketball stars and Howery does his best to make it work, but it depends utterly on NBA loyalty and fan-worship. It coasts along on recognition and sports star-status and not enough has been done on the script.