Two healthy young people sign up for a trial to test a new antidepressant. As the dosage is increased they fall in love - but is it real? If your happiness is artificially created, how can you trust your feelings?

This is one of the questions posed in the first production of the New Year at The Abbey Theatre by Lucy Prebble.

The Effect was first performed at The National Theatre in 2012 and is a clever examination of the mysteries of the mind and the nature of depressive illness. It questions whether antidepressant drugs are useful and asks whether being depressed is just a natural part of the human condition, and not an illness.

In the play a leading pharmaceutical company is sponsoring a drugs trial to test for possible side effects. The psychiatrist leading the trial is Dr Toby Sealey, who works for the company and is convinced that there is a chemical solution to all mental health issues. To help him run the trial he brings in his former girlfriend, Dr Lorna James, who has lost her job at Barts Hospital because of her own mental health instability.

The two paid volunteers are psychology student Connie and drifter Tristan. They aren’t actually depressed but the drugs increase their level of well-being and soon they fall head over heels in love.

Director Chris Bramwell explains the central predicament: “Love is a phenomenon that intrigues us all. What triggers it, and why for some is it so fleeting and for others a longer lasting and more enriching experience?

“If you are being given an antidepressant containing dopamine, the hormone released when people are attracted to each other, is it possible to say whether the attraction is caused by the drug or whether it is happening naturally?”

This unexpected “side effect” causes problems for the two medics as well as the volunteers. Lorna, played by Joanne Emery, loses control of the trial because the volunteers fall in love.

This intriguing production may ask more questions than it answers, but it will certainly give you food for thought in the coming year. Please be aware that the play contains strong language and scenes of a sexual nature.

Performances take place in the Studio between January 19 and 27. To book tickets go to abbeytheatre.org.uk or call 01727 857861.