This is an extraordinary piece of work: an everyday story which is also a poem; a modern American drama steeped in Yoruba mythology; sophisticated, self-aware writing which is also simple and clear.

The Brothers Size, by Tarell Alvin McCraney, an ATC/Young Vic co-production, is the first part of this young American writer’s Brother/Sister Trilogy. Ogun and Oshoosi are two brothers living in Louisiana. Ogun is the reliable, hard-working older sibling; Oshoosi is on parole, more fun-loving and less keen to take responsibility. Elegba, Oshoosi’s cell-mate, presents him with possible trouble in the form of a clapped-out car and illicit drugs.

These three, superbly acted by Nyasha Hatendi, Obi Abili and Nathaniel Martello-White respectively, play out their relationships in the round within a freshly-drawn chalk circle, backed by discreet but fitting music played by Manuel Pinheiro.

The interest of the play is entirely in the intensity of the relationships, especially the fierce but problematic bond between the brothers. Yet McCraney plays with the idea of theatre, having his characters speak stage directions so that we are never allowed to forget that this is a story, a ritual. There is a self-consciousness about the characters’ particular brand of African-American English too; several times they specifically refer to - even make fun of - the choice of a word or phrase.

The helpful Young Vic website provides the information that Ogun is the Yoruba god of iron, that Oshoosi, the name of his brother, means “wanderer”, and Elegba was the deity of the crossroads who offered choices and temptations.

But the characters are recognisable from any society; the brothers with their shared memories and blood-thicker-than-water closeness (which ironically leads to a desire to save rather than believe Oshoosi on Ogun’s part) and the friend who wishes to be at least as influential as a brother, could be from any time or place. Ogun tries to pull Oshoosi into line by surrogate parenting before accepting him for what he is and - as they sing “Try a Little Tenderness” together in bantering harmony - revealing the depth of his familial feeling.

Bijan Sheibani’s sympathetic direction allows the play to speak freely, powerfully, in full poetic voice.

- Heather Neill