STELLA ARTOIS BLACK / THE BLACK DIAMOND

Diamonds, thieves, treachery and intrgue: Contagious was invited along to Stella Artois Black's interactive event, The Black Diamond, a seven-part interactive story set in the 60s running from July 6-21 in London, staged in association with immersive theatre innovators Punchdrunk.

The follow up to last year's interactive theatrical experience, The Night Chauffeur, guests gathered at a secluded, unmarked East London studio for the first installment of the story, The Party, where our hero, young diamond cutter Jacques Ferre, is to propose to his beloved, Cecile.

Meticulous mise en scene, including old 60s postcards, furniture and posters, along with actors in period garb, all created an atmosphere of swinging intrigue. One actor quietly pressed a rose petal into the hand of Contagious' companion with a whispered: 'This is from Jacques. The answer is yes,' before disappearing into the crowd. Other audience members were deep in conversation with actors; one said she'd avoided the queue for entry, led through a back entrance by another accomplice in the action.

The crowd was then hushed and told to crouch as a blindfolded woman - Cecile - was led in, part of a surprise birthday party. Shortly afterwards, the revellry turned serious and joyous as our hero, Jacques, proposed, only for the ring to be dropped and then - gasp - stolen, with the crowd asked to leave the party until the ring could be found.

Contagious and fellow audience members then waited outside for more, before dispersing as the action came to a rather anti-climactic end.

Left wondering, we turned to the website for more detail about the mysterious events. There a noir-esque, slick website and voiceover explains the mystery further: 'On a quiet night under a still moon, Jacques Ferre proposes to his love with a black diamond. A thief rips it out of his hands and Ferre makes a curse. "Whoever has that diamond will be shaken from their dreams by the hand of misery. They will be alone, they will be betrayed, they will be heartbroken, until time, the only true god, restores it to me."' 

For the next six years, the diamond continues to be passed from hand to hand - no one can keep hold of it, despite the best efforts of the drama's cast: the professional thief, the treacherous brother, the seductive cabaret singer, the wealthy coward and, for those about to take part, you.

The site details how to enter for a chance to get tickets, more about the story, its protagonists and a map of East London with forthcoming episodes about how The Black Diamond's interactive storyline will play out.