The Crown viewers have spotted a historical error in a first look image of Princess Diana from season four.
Ahead of the fourth season airing on Netflix in November, a new series of images were released on Tuesday, giving fans a first look at Gillian Anderson as Margaret Thatcher, as well as Olivia Colman as Queen Elizabeth and Tobias Menzies as the Duke of Edinburgh, who are reprising their roles.
However, it was an image of Lady Diana Spencer, played by newcomer Emma Corrin, that attracted attention from eagle-eyed fans who spotted a historical mistake in the background.
Season four is set during the end of the 1970s, but one picture in which the future Princess of Wales is seen being photographed by paparazzi includes a modern London red bus driving past in the background.
“Season 4 of The Crown is out in November - I wonder if the time-travelling new Routemaster bus will also be in it?!,” one viewer tweeted.
Watch: The Crown exhibits Princess Diana's most iconic moments
“Not the Boris bus in the background of the Diana shot though,” another social media user wrote.
The Crown season four will see the Queen looking to safeguard the line of succession by finding a bride for Prince Charles (Josh O’Connor), who is still an unmarried bachelor at the age of 30.
The series also charts the growing tensions between Thatcher and the queen, as the prime minister leads the country into the Falklands War.
The Crown also stars Helena Bonham Carter as Princess Margaret, Erin Doherty as Princess Anne, Emerald Fennell as Camilla Parker Bowles and Marion Bailey as the Queen Mother.
The new season will be available to stream on Netflix from 15 November.