@ Tron Theatre, Glasgow, until Sat 28 Feb 2015 (and touring)

What’s the difference between feelings caused by brain chemicals and those produced by your environment? If you can control the chemicals in your brain with drugs, then are the feelings you had real? These are the main ideas explored in Firebrand‘s revival of Lucy Prebble‘s involving dissection of love and pills, The Effect.

Scarlett Mack and Cameron Crighton play two drug study volunteers, signed up to a four-week residential trial to test a new anti-depressant. As they get to know each other, a relationship sparks, but they can’t tell whether their attraction is down to the dopamine side effects of the drug or genuine feelings. It’s a tough question and carefully unpacked with the help of some thoroughly-researched theory. After all, how can you fall in love without hormones?

A neat set of character parallels allows a simultaneous exploration of the causes of depression, via the relationship between Pauline Knowles‘s psychiatrist and her manager (played by Jonathan Coote). Do you blame your environment for depression or is it a chemical reaction that would be naive not to treat medically? We are guided through public perceptions of mental health and the role and motivations of pharmaceuticals.

With the formula clearly set there’s a concern that the plot might become predictable – an epic TED talk on neuroscience, with the characters becoming vehicles for conveying the bucket-load of information Prebble has us consider. However, the play manages to side-step this trap after getting the inevitable out of the way. We already know the premise of the show, and that the main characters are destined to fall for each other, wondering if they are really in love. What follows is a compelling story that is dramatic, funny and moving; brought vibrantly alive by dynamic staging and energetic performances.

Everyone wants to know how love works, which is why the scientific backbone of the play is still so engaging. It is thoroughly entertaining and beautifully balanced.