Purge is a piece of theatre which explores how social networking sites have become an integral part of our lives.

In 2011 performance artist Brian Lobel decided to create art based on his Facebook friends.

Across the space of five days he gave strangers one minute to decide which of his 1,300 friends to keep or delete.

Before starting the purge he messaged his friends to tell them and said they could send him a message to read out in his or her defence.

What resulted was 800 emails, 2,500 comments from people watching on a live stream and some broken friendships.

Purge, which was performed at Battersea Arts Centre on Friday, sees Lobel revisit the subject matter and tell the tale of what ensued after his Facebook cull.

The piece features only Lobel, his laptop, a powerpoint presentation and a few laminated signs, with Lobel taking on the role of story-teller.

Audience members are given the chance to shout out their own reasons for deleting friends, while one brave viewer steps up to delete one of her old schoolfriends.

Next we are handed laminated signs.

Lobel invites us to vote whether we believe the friend was kept, deleted.

The messages his friends sent beforehand are read out, with interesting results.

Some are angry, a few sentimental and others are just plain weird.

But in some circumstances Lobel discovers he was deleted pre-emptively before he even began the piece.

Interweaved within the performance is the sub-plot of Lobel's relationship with ex-boyfriend Grant.

Following Grant's death, he discovered Grant deleted him from Friendster in 2010, which inspired the creation of Purge.

Battersea Arts Centre, Lavender Hill, Battersea, visit bac.org.uk