Although not thought to be a direct replica of any of the mother-of-two's dresses in particular, the one-shoulder style and floral pattern is no doubt a sartorial tribute to the Princess of Wales' love of all things Catherine Walker.
Corrin, who also boasts the royal's famous '80s bouffant in the images, can be seen waving to crowds with extras taking on the role of camera-bearing paparazzi surrounding her.
Though it's not the first time the British starlet has excited fans of the Netflix series, as she was photographed filming with co-star Josh O'Connor, who plays Prince Charles, in Spain last October.
The small screen duo could be seen recreating the former couple's 1983 royal tour of Australia which saw them don near-identical outfits to the get-ups their regal counterparts wore to visit Uluru at Ayers Rock.
Viewers will be introduced to Princess Diana in the upcoming season with the focus shifting to focus upon Prince Charles' tumultuous love life.
Speaking about taking on the role of Diana, Corrin said in a statement released by Netflix: "Beyond excited and honoured to be joining The Crown for its fourth season."
"I have been glued to the show since the first episode and to think I'm now joining this incredibly talented acting family is just surreal. Princess Diana was an icon, and her effect on the world remains profound and inspiring. To be given the chance to explore her through Peter Morgan's writing is the most exceptional opportunity, and I will strive to do her justice!"
With the release date of season four yet to be confirmed (it's not likely to grace our laptop screens until late 2020), we've go plenty of time to rewatch all three seasons a couple (read: several) more times.