"That's lazy and convenient thinking," says the mysterious American in Alexi Kaye Campbell's new play.
The setting is a Greek island in 1967 where middle class Londoners Charlotte (Pippa Nixon) an actress, and her husband Theo (Sam Crane), a playwright, are having guests stay at their idyllic house, rented from a local family. It's a place where the muse can inspire, finds Theo. Though writing has to take a pause during this visit by the aforementioned American, Harvey (Ben Miles) and his wife June (Elizabeth McGovern) who Charlotte met in a taverna.

It emerges that Harvey is some sort of CIA troubleshooter - or troublemaker - whose job involves deposing governments the United States considers to be counter to its interests, such as the Greek government in 1967. And it's here that Charlotte expresses doubts about America's role in the world and Harvey chides her for the lack of rigour in her thinking.

But when he orchestrates an impromptu negotiation between the English couple and their Greek landlords to buy the house for a song because the owners want to emigrate, the influence of this American seems much more benign.

It's during this scene - in which greed overcomes English middle class good intention - that Simon Godwin's superbly acted production peaks. Miles is pure American charisma and McGovern does wonders with the underwritten role of the supportive wife. Where it all begins to falter is in the second act when the play attempts to find moral equivalence between the deal Charlotte and Theo struck to buy the house and, um, the bloodshed brought about by Harvey's latest adventure, deposing Alllende in Chile and installing a fascist, murderous government.

If Campbell wants to implicate England's smug middle classes for having a more corrosive effect on the world than they would ever like to think, I have no problem with that. But he seems to be saying that they are as bad as what happened in Chile. Which is surely just lazy and convenient thinking.