A dark, razor-sharp thriller by Emmy-winning writer of Succession, Lucy Prebble. The Effect dives into the chemical nature of love through the lens of a clinical drug trial. Connie and Tristan enter a study for a new dopamine-regulating antidepressant. They fall in love. Or do they? As dosages rise, desire and obsession intensify, and the boundary between genuine emotion and altered chemistry begins to blur. This provocative and timely co-production between Rumble Theatre and ITSAZOO Productions asks: If you can't trust your heart and you can't trust your mind—what’s left?