Tristan and Connie are two passionate volunteers. They decide to join a medical experiment testing the effect of antidepressants. Relationship between them grows in intensity, as do the doses of medication. The couple breaches hospital regulations, and breaks their own limits. Suddenly it is no longer clear where their emotions actually come from. Is it in their minds under the right influence of drugs? Or is it indeed in their hearts, for each met the right person? What portion of the love is genuine and what is just a side effect? Dr. James, the lead physician of the project, however, herself experiences depression and goes through personal crisis. She thinks medical ethics have gone too far. Yet the senior consultant, Dr. Tobby considers such infatuation to be the desired sided effect of a new drug.

The play by the award-winning British playwright Lucy Prebble explores the limits of science and ethics, as well as those of our own emotions. In the UK The Effect received the 2012 Critics’ Circle Award for Best Play.