A stage play adapted into a glorified acting showcase, August: Osage County is very pleased with itself indeed. Tracy Lett’s dark Broadway triumph spans three generations of a dysfunctional Oklahoma family, their lives revolving around cancer-stricken, drug-addicted matriarch Violet (Meryl Streep).

A superb Julia Roberts is hardened and biting as Barbara, the eldest daughter on the cusp of divorce. Abigail Breslin is her precocious teen daughter and Benedict Cumberbatch is predictably fantastic as the gentle and clumsy cousin, whose one simple desire for happiness may soon be ruined.

However, the wonderful cast can’t distract from the fact that director John Wells remains constrained by the movie’s theatrical origins. Lett’s razor-sharp words pour down like acid rain, scarring everyone they touch. However, the sterling performances cannot detract from the stagey structure, heavily reliant on stilted monologues.

Of course, Meryl is a tour de force. She portrays Violet as a howling, clawing, snarling force of nature, at once loathsome and pitiful. Unfortunately August: Osage County has the same innate flaws as the central protaganist. It is fascinating and complex – but intolerable in its deafening need to be noticed.