“The Effect” at the Lyttelton, National Theatre

Neil Dowden on the South Bank
13 August 2023

Premiered to acclaim in 2012 in the intimate Cottesloe (now Dorfman), Lucy Prebble’s The Effect returns to the National Theatre this time in the large Lyttelton. The play’s microscopic focus on the mood swings of the two protagonists who seem to fall in love during a drug trial demands the audience’s close attention, so director Jamie Lloyd has transformed the usual proscenium-style layout for a traverse performance, with some of the audience sitting where the stage usually is. The result is a heart-pumping show in which we feel emotionally involved – albeit often uncomfortably – in a human behavioural experiment.  


Paapa Essiedu and Taylor Russell.
Photo credit: Marc Brenner.


The premise is that a young man (Tristan) and woman (Connie) – previously unknown to each other – are taking part in an in-patient clinical trial for a new antidepressant at a laboratory. Hackney streetwise Tristan is doing it for the money (he has participated in similar previous experiments), while Canadian psychology student Connie’s motives are less clear. They have very different backgrounds and personalities – he is more spontaneous and rule-breaking, and wants to go travelling, while she is more introverted and cautious, and seems to be having an affair with an older male academic who has a family – but they hit it off big-time. The question is though: is the chemistry they have together natural or pharmaceutical? 

In charge of the trial are two doctors who, it transpires, are not just disinterested scientific observers as they themselves have a shared sexual past. Psychiatrist Lorna James – herself a sufferer from depression – while abroad at a conference had a fling with Dr Toby Sealey who prefers one-night stands to relationships and who as the pioneer of the new antidepressant has now got her the job at the lab. He has a vested interest in the drug succeeding, while she thinks Tristan and Connie’s positive energy and heightened awareness could just be strong mutual attraction. It is complicated by the fact that one of them may be taking a placebo, but there are signs that the experiment is spiralling out of control as emotions intensify.  


Kobna Holdbrook-Smith as Dr  Sealey.
Photo credit: Marc Brenner.


The Effect touches on intriguing questions of medical ethics, moral dilemmas, and personal/professional conflicts. Can depression be treated as simply a chemical imbalance in the brain rather than as a psychological condition? Is the prototype drug a “Viagra of the heart”? Is love just a rush of dopamine? It only goes so far though – and there is nothing about the dodgy role of Big Pharma in developing certain medications. But the are they/aren’t they, will they/won’t they questions about the central relationship engage our feelings as the play moves towards its poignant ending. 

Prebble – who has also had notable theatrical successes with Enron and A Very Expensive Poison – has more recently focused on writing for television with big hit series Succession and I Hate Suzie. Interestingly, she rewrites her plays when they are re-staged, updating where necessary and also tailoring the dialogue to the current actors – in this case an all-black cast, including one Canadian.  

Lloyd’s gripping 100-minute interval-less production maintains the tension throughout, with all four actors on stage virtually the whole time (the ones involved in a scene are spot-lit), as the two grey-sweatsuited “guinea pigs” are “caged” between the two doctors who sit in a plastic chair at each end in Soutra Gilmour’s stripped-down design. The only prop is a bucket from which a human brain is plucked. Jon Clark’s white LED lighting flashes are like electrical impulses sent from neurons, amplified by Michael “Mikey J” Asante’s nervily pulsating score and George Dennis’s throbbing electronic sound.  

Paapa Essiedu (the RSC’s first black Hamlet and more recently star of TV drama serial The Capture) gives a dynamic performance as Tristan, showing how his initial cocksure flirtatiousness gives way to aggressive obsession and then desperate neediness as The Effect takes over. He is matched by Vancouver-born Taylor Russell (star of horror romance film Bones and All and Netflix sci-fi series Lost in Space), making a confident stage debut as the conflicted Connie who eventually casts aside her inhibitions and doubts to embrace her emotions. Michele Austin is excellent as the sceptical Dr James who puts fellow-feeling before scientific rigour, in contrast to Kobna Holdbrook-Smith’s deliciously duplicitous Dr Sealey whose smooth charm masks a chilling emotional detachment.