Fremantle Theatre Company’s latest show, The Effect, by British playwright Lucy Prebble, is a perfect example of the company’s strengths. Its artistic director, Renato Fabretti, looks for successful, meaty 21st century work (The Effect premiered at Chichester and in the West End in 2009) with important themes and strong performance potential.Prebble, whose credits include the award-winning play ENRON and a continuing role as writer and co-executive producer on television’s global smash Succession, delivers both.A tense, multi-faceted medical procedural/thriller set in a clinical drug trial hospital, it takes a deep dive into the ethics of experimentation in novel medication and treatment, especially, and in this case, for depression.Connie (Catlin Ashley Thompson) and Tristan (Adam Sollis) are being inducted into the clinical trials for a new psychotropic medication that will be administered in increasing doses in a closed, live-in environment.The programme has been devised and is supervised by a psychiatrist, Dr Lorna James (Carla Bonner), who in turn, is overseen by Dr Toby Sealey (Oliver Wenn), with whom she has had a long, somewhat fraught, and clearly not entirely professional relationship.Tristan is eloquent, flirtatious and not a little manic, with a history of psychological disorder; Connie, a psychology student herself, is bright, troubled, teetering on the precipice of depression.In the normal course of events, they are two people who would not, and probably should not, be drawn together. But in the isolated environment they inhabit, and as the doses of medication they take increase from 25 to 50 to 100 mg and beyond, there’s inevitability to their growing, risky relationship.The doctors, too, have personal baggage to deal with, exacerbated by their conflicting view of depression and the efficacy of medication to cure it; the academic tension of their argument is played out by the progress of their patients.There’s a fair dose of academic theory to take in as The Effect progresses, and my tendency to drift off in lectures was a threat at times, but Prebble is dramatically savvy enough to largely avert that danger.In any case, the four actors give you plenty to keep your interest; Bonner, Wenn, Thompson and Sollis are magnetic performers, with the mix of stage and screen experience necessary to make the most of their characters and the text.Pippa Grandison has fashioned a three-decade long career as an actor and, lately, director, and she places the action and her performers in the architecture of the grand old 1896 gold rush hall with an astute and seasoned touch.The mood Grandison and her cast creates is captured beautifully in the accompaniment by the cellist and composer, arranger and sound designer Anna Sarcich, perched high on the hall’s balcony and playing a score with snatches of everything from Bach’s Cello Suite No. 1 to INXS’s Never Tear Us Apart. A lovely touch.Fabretti’s stage design is functional and convincing, Matthew Erren gives it deft lighting. All in all, The Effect is a tense, engrossing and relevant piece of quality, mature theatre.You’ve got to hand it to FTC.The ebullient Fabretti and his team have created a hot item in Victoria Hall that fits the renascent Fremantle city centre like a glove.Since its launch with the smash hit The Other Place in 2018, FTC have quickly built a broad and committed audience with an intelligent repertoire including Gillian Greer’s Meat and Reg Cribb’s marvellous Last Train to Freo, as well as revitalising the holiday season’s Shakespeare in the Park.In many ways FTC, along with the equally interesting Theatre 180, whose The Children, I and You and Blue/Orange dovetail with their hugely popular CineStage mixed-media productions, have taken up the mantle of Perth’s former second-stage companies like The Hole in The Wall, Perth Theatre Company and Deckchair Theatre whose progressive loss has been sorely missed over the past few decades.I hope the energy and vision of these companies’ leadership is supported by audiences and funding bodies to give us more and more of the text-driven, mature theatre we have enjoyed less and less of in recent times.The Effect continues at Victoria Hall until 3 June 2023.