THE Effect is a romance set in the world of the pharmaceutical industry. It offers a cocktail of emotions - laughter, tears, fear and indignation. And though its ending is not altogether convincing, it is still the best production of 2016 so far, elevated for the most part by the intelligence of Lucy Prebble's script, the air-tight direction of Tracie Pang and a quartet of actors whose combined charms can persuade any government to purchase any drug at any price.

The story centres on an ebullient young man (Linden Furnell) and a level-headed young woman (Nikki Muller) who separately volunteer for a drug trial in a laboratory. The two meet cute - they flirt as they hold urine samples - and infatuation quickly escalates into full-blown passion.

But the drugs administered to them are supposed to boost their dopamine levels, that hormone in your body that makes you feel happy. So they soon start to wonder if this is really love or simply the effect of the drug. After all, the effects of love on the brain are similar to the effects of drugs on it.