The Advertising Standards Agency (ASA) has announced that it is spearheading an investigation into the publicity poster for a critically-acclaimed play in London, following an official complaint from a tube traveller that the sexually-suggestive intimacy displayed in print was “offensive”.

Mies Julie became an instant classic after an extremely successful run at the Edinburgh Festival Fringe, and has since gone on to become the most successful play at Riverside Studios over the last five years. It is a reworking of August Strindberg’s play Miss Julie, which is set in post-apartheid South Africa.

However, the Independent revealed that advertising for the play – which portrays a topless man straddling a fully-clothed woman – had angered someone on the London Underground, and meant the ASA would be checking to see “whether the ad was offensive and unsuitable for display where it could be seen by children”.

Defending the poster, William Burdett-Coutts, director of the Riverside Studios, told the newspaper that the claim was “extraordinary”. He said: “It’s emblematic of the show. It’s not offensive. It’s bizarre. It’s the first time I’ve had a complaint like this in 35 years.”