Actor-turned-playwright Oliver Cotton’s new work poses a problem for reviewers: how much to divulge? It hinges on big revelations, and as much of the meandering two-hour-plus play is interminable preparation for said revelations, it would seem cruel to spoil them, snatching away the ribbon just as you approach the marathon finishing line.

Yet the problem with Cotton’s piece is that it takes so long getting to its twists, there’s little time to deal with the fallout, so denying us the meat of the drama. Instead, his set-up has a self-indulgently epic quality that makes Scorsese look positively epigrammatic.

In 1980s New York, an elderly Jewish couple’s comfortable life is interrupted by the sudden return of Joe’s estranged brother, who disappeared 30 years earlier. Wild-eyed raconteur Billy (Cotton) shares his strange tale: while holidaying in Daytona Beach, Florida, he spotted a key figure from their collective past and took drastic action. Billy’s lengthy yarn would be more engaging if Harry Shearer’s bland accountant Joe communicated an interesting response, but he’s hamstrung by Cotton and director David Grindley’s indecision: is this high drama or black comedy? It falls somewhere in between, neither wholly believable nor particularly affecting.

The second half – a similarly protracted saga – is far more effective due to excellent Maureen Lipman providing the necessary range of emotion, from sardonic passive aggression through to vehement, naked grief. But she can’t escape the fact that the first-half twist is essentially a red herring, with the expected debate concerning trauma, revenge, reinvention and morality mired in predictable melodrama.

The ambitious ideas are never fully developed, and the play’s inciting incident is too similar to Dorfman’s far superior Death and the Maiden. The real revelation here is that Cotton the playwright has yet to match the heights of Cotton the actor.

Until August 23.