G illian Anderson has never really been a movie star. Instead she belongs to the pantheon of greats best seen in the boxes in our living rooms – think the Jon Hamms or the Sarah Lanchashires, people we don’t tend to like in 90-minute chunks, but rather in weekly installments, delivered annually, sometimes with ad breaks. The cynical professionalism of The X Files ’ Dana Scully led to the pansexual cool of The Fall ’s Stella Gibson, which led to the deadpan comedy of Sex Education ’s Jean Milburn and the campy severity of The Crown ’s Margaret Thatcher . Anderson is to TV what DiCaprio is to cinema – built for it, comfortable in it, always able to catch its trends and waves. And that’s why it’s so refreshing to see her become the darling of the Cannes Film Festival this week, in a movie that finally taps into that frosty, slightly off-piste allure that few filmmakers have ever successfully harnessed.…