Comedy and tragedy make unsettlingly close bedfellows in Donna Franceschild’s big, popular drama about the precarious revival of a radio station in a Glasgow psychiatric hospital. And although Mark Thomson’s slick, pacey staging – a co-production between the Lyceum and Glasgow’s Citizens Theatre – brings plenty of laughs, there’s an undercurrent of threat and unpredictability, even violence, that raises darker questions about patients’ freedoms, and about the sanity of the mental health system itself.

But make no mistake – it’s a hugely enjoyable evening, full of thought-provoking fun and often rowdy laughter. Based on scripts from Franceschild’s successful 1990s BBC TV series of the same name – but substantially rethought for this 21st-century theatrical reincarnation – it follows failed DJ and double-glazing salesman Steady Eddie McKenna (a quietly strong performance from Iain Robertson) as he brings his cherished collection of Marvin Gaye, Otis Redding and Sam Cooke LPs to entertain the patients in the St Jude’s mental institution on its almost-defunct hospital radio system.

It’s not long before the new arrival starts to transform the lives of patients – from hyperactive young Campbell (a brilliantly volatile Brian Vernel) to cleanliness-obsessed Rosaline (in a touchingly warm performance from Caroline Paterson). But as their confidence, creativity and involvement increase, so does conflict with the institution’s subtly repressive management.

Franceschild is good at pointing up blurred lines between sanity and insanity – in the alcoholism of the supposed level-headed Eddie, for example, or the barely suppressed violence of nurse Stuart. And she’s keen to show the role that circumstance has played in the patients’ conditions, for instance in the understandable reaction to abuse exhibited by the fragile Francine, played with tenderness by Helen Mallon.

But she also seems keen to cram as much as she can into what feels like quite a long two and a half hours. As more and more of the patients’ back stories are revealed, Franceschild’s narrative thread seems increasingly to lack focus – by the end, we have so many tales to take on board that a sudden tragedy goes all but unnoticed.

Nevertheless, it’s a powerful, thoroughly entertaining evening, and Thomson draws exceptionally fine performances from his extremely strong cast. Without the slightest hint of voyeurism, it’s as though we can only truly find order and meaning by staring into the chaos.

Taking’ Over the Asylum continues at the Lyceum Theatre until 6 April