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Shots of the inside of the Scarif base featuring the railway station were filmed at the Canary Wharf London Underground station. The budget did not allow for creating this additional set, so director Gareth Edwards opted to use Canary Wharf station for its strikingly futuristic design. Production could use the site only at night between closing and opening hours, leaving only a few hours for set decoration and filming. Since everything had to be done in complete secrecy to prevent internet leaks, props and costumes had to be smuggled in and out when there were passengers present. The most frustrating thing according to Edwards was that they were filming a Star Wars movie in such a public place, and could not tell anyone.
Gareth Edwards and his creative team discovered some old film canisters while rummaging around the Lucasfilm warehouses. When he asked what they were, an employee said they were old Star Wars: Episode IV - A New Hope (1977) footage. The discovery led to the inclusion of unused Episode IV material featuring Red Leader and Gold Leader in this movie.
R2-D2 and C-3PO have a brief cameo, making Anthony Daniels the only actor to appear in every movie. (He appears as another character in Solo: A Star Wars Story (2018).)
Darth Vader's appearance in this film is meticulously patterned after his look in the original Star Wars: Episode IV - A New Hope (1977). While Vader's chest plate is uncovered in Star Wars: Episode V - The Empire Strikes Back (1980) and Star Wars: Episode VI - Return of the Jedi (1983), his costume initially had his Sith robes draped over his shield, as well as red lenses in the eye holes of the mask. Considering this film takes place mere days before the original film, the costume designers recreated Vader's look down to the last detail.
Diego Luna, who plays Cassian Andor, improvised K-2SO's slap across Cassian's face on Jedha, and Alan Tudyk improvised the line "And there's a fresh one...".
Anthony Daniels was jokingly disgruntled that Alan Tudyk was allowed to play K-2SO in the relative comfort of a motion-capture suit, whereas Daniels had to endure years of discomfort and injuries in the C-3PO costume. Daniels laughingly cursed at Tudyk after Rogue One's premiere. Tudyk later said that a "Fuck you" from Daniels was one of the highest compliments he had ever received.
Warwick Davis: The Star Wars veteran actor plays Weeteef Cyu-Bee, one of Saw Gerrera's militia members.
Rian Johnson: Star Wars: Episode VIII - The Last Jedi (2017) writer/director plays an imperial trooper controlling the Death Star's superlaser.
Phil Lord, Christopher Miller: as the Death Star crew members manning the super laser shaft. Lord and Miller were set to direct Solo: A Star Wars Story (2018), before being fired due to creative differences.