There are plenty of themes swimming around in Sam Mendes’s sprawling, uneven Empire of Light, but few coherent ideas linking them. Set in the 1980s, in the kind of pursed-lipped and sanctimonious British seaside town that wears its former glory like a long outdated party frock, the film awkwardly slings together mental health issues and racially motivated violence, then ties it up with a rather glib point about the unifying power of cinema.

Olivia Colman plays Hilary, a troubled front-of-house manager at a seafront picture palace, who forms a romantic bond with a much younger employee (Micheal Ward). Colman is a phenomenal talent and Ward shows potential, but even so, the relationship between them struggles to convince as anything more than a plot device. This is the first film that Mendes has directed from his own screenplay (he had a co-writing credit on 1917), and for all its visual flair, courtesy of veteran cinematographer Roger Deakins, there’s little to suggest that Mendes has the writing chops to match his directing skill.

• In cinemas from 9 January