Gracie Atherton is around 60 years of age, very attractive and with a sparkling personality (played by a gorgeous 62-year-old Julianne Moore). She is happily married to Joe (Charles Melton), a quietly confident and handsome man of Korean descent 23 years her junior. They have three adult children, the youngest one about to graduate from college. Nothing unusual there: the real-life Brigitte Macron is a quarter of a century older than her husband, the president of France. But there’s more. Gracie and Joe started their relationship in the ’90s, when then the male was aged just 13.

The romance became a national scandal. Gracie was consequently jailed and gave birth from prison, a newspaper reveals. None of that stopped the Gracie and Joe from being together. Their relationship remains as strong as ever, it seems. So much so that they invite famous actress Elizabeth Berry (Natalie Portman) to spend a significant amount of time with them, conducting extensive interviews with every member of the family. She is preparing to play Gracie in a film adaptation of her controversial life. Presumably she wants a full-on method acting immersion. She’s in for a wild ride.

Elizabeth becomes increasingly fascinated with Gracie, who describes herself as “unapologetically naive”. She feels neither guilt nor regret about her relationship with Joe. Neighbours beg to differ. She receives a package of faeces in the post, in the film’s very first scene. It is not entirely clear whether Elizabeth’s courageous efforts to understand Gracie’s psychology are merely because she wants to deliver a more credible performance. Or maybe there are more sapphic vibes in the air? Perhaps competition? Or maybe even a dash of narcissism? Does Gracie see the famous actress as a younger version of herself? Whatever the answer, the two women bond. Elizabeth’s elicitation technique becomes unrestrained (and the questions more intrusive) as she speaks to Gracie’s old family (her ex-husband Tom and the children of around her new husband’s age, whom she abandoned two decades earlier).

Gracie subverts the American family in many ways: it was the female that abandoned the husband, and in favour or a much younger and non-white male. If that wasn’t enough, throw in a touch of paedophilia, sexual abuse and maybe even incest. Gracie’s son Geordie (Cory Michael Smith), from her first marriage, tells Elizabeth that his mother is a much darker and more disturbed person that she may seem on the surface, Elizabeth takes notes duly. She could become irrevocably involved with Gracie and her families in more ways than one.

Haynes’s is recognised for his slow burn stories with credible characters, and for giving viewers enough time for reflection. May December is no different. This drama develops at an unhurried pace. The plot is real enough for resent-day US. And there are moments for depressurising, particularly as the more homely Joe looks after his plants and animals. On the other hand, May December does not subvert any paradigms – something Haynes hasn’t done in the past three decades (since he directed Poison, in 1991). Not even Carol is a particularly dirty movie. His latest feature portrays small fractures of the nuclear family, however it does not shock, entire or even move viewers. Neither are the dilemmas particularly new, nor are they dissected in a new light. The script isn’t very imaginative. The outcome is a mostly lukewarm drama, with some a few good moments thrown in (Joe smoking marijuana on the rooftop of his house, and a very awkward dinner when Gracie’s two families meet are the biggest highlights). At least this is an improvement on the last movie that Haynes premiered at Cannes, 2017’s extremely conceited and mostly predictable Wonderstruck. It’s unlikely the director will return to the shape of his youth, but it would be nice it he became a little more audacious.

Juliane Moore is a long-time collaborator with Haynes. This is the fourth time she plays the lead in his films, after Safe (1995), Far from Heaven (2002) and Wonderstruck.

May December premiered in the Official Competition of the 76th Cannes Film Festival, when this piece was originally written. It shows at the the BFI London Film Festival in October, and then at the Best of Festivals section of the 27th Tallinn Black Nights Film Festival. In UK cinemas on Friday, November 17th.