Gloria Obianyo and Janie Dee in Speculations

I’M not sure why Torben Betts’s Speculations is billed as a political thriller. It focuses on imagined conversations between Robert Kennedy (Jolyon Coy) and Marilyn Monroe (Natalie Dunne) on the night she died, alongside a meeting between mafia boss Carlos Marcello (Ferdy Roberts) and President John F Kennedy’s assassin, Lee Harvey Oswald (Joseph Potter).

At the heart of the drama is investigative journalist Dorothy Kilgallen (Janie Dee), who in 1965 continued to speculate on these mysterious deaths and herself died in suspicious circumstance. Betts suggests she was silenced before she could reveal what she had discovered.

Kilgallen shares her theories with her childminder Flo (Gloria Obianyo), who is herself an aspiring journalist.

Monroe’s final hours are well-trodden territory – one only has to think of Sharleen Cooper Cohen’s misguided play Who Killed Marilyn?, starring Pixie Lott earlier this year. I wonder what possesses writers to keep revisiting the day of the film star’s death with nothing new to offer.

There’s a stellar creative team involved, with Trevor Nunn directing, but the storytelling is heavy-handed with too much exposition.

Lee Newby’s three revolves use Kilgallen’s New York apartment as the main location, deftly transporting us back in time to Monroe’s Los Angeles bedroom and a New Orleans bar. However, once we’ve been back and forth a couple of times, the device loses its novelty.

The action unfolds through these conversations, giving the piece a static feel with little tension. It’s well acted, but conspiracy theories have never held much appeal for me, and Betts’ fictionalised rehashing of history struggles to sustain our interest.

Until January 17
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