Speculations at Marylebone Theatre

By Maggie O'Shea 5 November 2026

Conspiracy theories remain popular because they occasionally contain elements of truth. The hypotheses presented by writer Torben Betts in Speculations – that Marilyn Monroe was murdered by the Kennedys and Lee Harvey Oswald did not act alone – are not new, and they endure because they seem just about plausible enough. Nonetheless, they remain just theories, and thus this production at the Marylebone Theatre – even in the hands of revered director Trevor Nunn – can’t help but feel like an overly melodramatic retelling of familiar conspiracy theories.

It’s 1965 and journalist and TV presenter Dorothy Kilgallen (a real historical figure) is just about to finish a book exposing what she says is a massive conspiracy linking the deaths of Marilyn Monroe, JFK and Lee Harvey Oswald. Though frightened she’s being watched, questions from her curious new childminder, Flo, prompt Kilgallen to recount two key scenes. Fragmented across the play, we see both play out: a confrontation between Monroe and Robert F Kennedy, and a clandestine meeting between Oswald and mafia boss Carlos Marcello.

Speculations is a deliberately chosen name: there is no solid evidence either of these meetings actually took place. But if this title suggests we’re in for a clever riff on the very nature of speculation – what people will believe and what they won’t – the play never lives up to this. Instead, the conspiracy theories become the story itself, without ever developing into particularly compelling drama.

The unconvincing premise that Kilgallen is spilling her big scoop to a total stranger is necessary because Flo is the audience stand-in. She’s sceptical and has to be won over by Kilgallen, so their conversation follows a predictable trajectory where Kilgallen talks of “waking people up” and Flo says things like: “I’m scared because I think you might be right – and I don’t want you to be right.”

The dialogue is no better in the flashback scenes, where Marcello delivers strained wisecracks, and Monroe says such overly familiar lines as “It’s like I’m living in a gilded cage” and “I do sin, but I’m not the devil”. Monroe fares worst; she’s reduced to the same naive, emotional, man-obsessed starlet we’ve seen in countless other portrayals, exacerbated by Natalie Dunne’s performance, which leans heavily into this characterisation.

One wonders if there’s a hidden meaning that’s buried too deep. Marcello repeats an aphorism just a few lines after Kilgallen employs it: “24…A wonderful age…A terrible age.” Is this a comedic throwback, or a clever reminder that Kilgallen is narrating our story – perhaps inaccurately? However, this idea is never explored further, with the play’s conclusion uninterested in ambiguity.

Janie Dee gives a confident performance as Kilgallen, offering steely intelligence and a believable descent into tipsiness. But taken as a whole, Speculations leaves one wondering what the production ultimately adds to these familiar theories. No matter how credible one finds those laid out, this play offers little that hasn’t already been explored in countless other accounts.

Maggie O’Shea
Photos: Helen Maybanks

Speculations is at Marylebone Theatre from 30^th October until 17^th January 2027. For further information or to book, visit the theatre’s website here.