Of all the star names in Christopher Nolan’s Oppenheimer – Cillian Murphy, Emily Blunt, Matt Damon, Florence Pugh, Robert Downey jnr et al – it is perhaps Tom Conti who is the most intriguing. Not so much for the actor himself as the character he plays. For Conti’s role is that of Albert Einstein, the 20th century’s most iconic and influential scientist, and the part is pivotal to the movie.

Typically for Nolan, the film plays out simultaneously in several timelines: one is before J. Robert Oppenheimer’s Trinity atomic bomb test in April 1945, and another is after it. Einstein features in the latter, talking to Murphy’s Oppenheimer by a pond in Princeton. We don’t initially hear what they’re saying, but the import of the conversation is clear both from the body language and the fact that they’re being watched at a distance by Lewis Strauss, Downey’s hawkish proponent of second-generation H-bombs.

The Telegraph London