If you've been following this Netflix series from the start, you'll know that it's taken us through many eras, from when Elizabeth was a young woman, new to the throne and working alongside Winston Churchill, to the trials of Princess Margaret, and the coming of age of Prince Charles.
Season 4 has been much anticipated because we head into the 1980s, with Margaret Thatcher in 10 Downing Street and Lady Diana meeting and becoming engaged to Prince Charles after a brief romance.
Have a look here at the trailer..
Maria says she's enjoyed it far more than Season 3 (which seems to be the general consensus) and she says the performances of Emma Corrin (Diana) and Gillian Anderson in particular stand out. Have a listen here to her chat with Ollie and me this morning on The Big Breakfast Blaa..