Recent 'Doctor Who' casting news revealed that Millie Gibson will be leaving her role as Ruby Sunday on the BBC's long-running sci-fi series. Gibson, who joined the show in the latest Christmas special, will only be part of the show until early in the 15th season. The marque role of the Doctor's companion will be taken over by Varada Sethu, known for her work in 'Andor' and roles in 'Jurassic World Dominion' and 'Now You See Me 2'. Sethu is set to star alongside the incoming Doctor, played by Ncuti Gatwa. Fans awaiting the next season of 'Doctor Who' can look forward to its return, with episodes airing on BBC and internationally on Disney+. For dedicated followers, "The Complete New Who Years" Blu-ray collection is also available.

Who is the new companion in Doctor Who?nVarada Sethu will be taking over as the new companion in 'Doctor Who', accompanying the Doctor, portrayed by Ncuti Gatwa, from the 15th season onwards.

As additional context, 'Doctor Who' is a British science fiction television program produced by the BBC since 1963. It follows the adventures of a Time Lord called "the Doctor," an extraterrestrial being with a human appearance, who travels through time and space in the TARDIS, a time machine that looks like a British police box. The show has become a significant part of British pop culture and has gained a cult following worldwide. The Doctor often takes on companions during their travels, and the character of Ruby Sunday, who will be leaving the show, is one such companion.