Mud opens straight into the best Stand By Me, boy’s own adventure territory. Our hero is sweet 14 year old Ellis from Arkansas, a closet romantic, given to punching High School bullies twice his size to defend the honour of his crush, May Pearl. Ellis goes nowhere without his trusty friend Neckbone (Nope, us neither. Maybe the family dog named him?), who sports the blonde crew cut ‘n’ freckles prerequisite to all kid sidekicks.

Neckbone is eager to show Ellis a Big Secret. Sneaking off behind their folks’ back, they steam up river in Neckbone’s motorlaunch, for this is Hicksville USA where kids ride motorcycles and slump nonchalantly in the back of pick-ups. Landing on a deserted island they head inland where Neckbone reveals – ta dah! – a speedboat perched half way up a tree, a relic from a flood. Except it isn’t so secret. It’s inhabited by wild-eyed, wild-haired dirt-bag, Matthew McConaughey.

Matt introduces himself as Mud. Mud is holed up in the tree-boat waitin’ fer his girlfriend, Juniper, to come join him. What kind of psychedelic, home-made moonshine are these people drinking? Mud is a persuasive beast and soon has Ellis ferrying back and forth to the island, fetching him food and parts to fix the broken boat. Then sure enough Juniper, Reece Witherspoon in best pink bra-strapped, white-trash mode, arrives in town. Honoured to play cupid, Ellis unquestioningly channels notes between the pair until Mud’s mug starts appearing on Wanted posters.

Part adventure, part childhood nostalgia trip, Mud is so atmospheric The Sloth was in need of salt tablets and mozzie repellent. Go see. Just don’t get carried away and rename your kid Fannie Lou.

UK release 10 May