Sacha Dhawan, the latest actor to step into the villainous role of the Master on Doctor Who, recently starred in a video explaining the history of the Master and his relation to the Doctor. The Master has been the nemesis of the Doctor throughout the show's long history, but the role originated in 1971 with Roger Delgado, who portrayed the Master until 1973.

After that, a series of actors took on the role, including Peter Pratt, Geoffrey Beevers and Anthony Ainley. The Master continued to torment the Doctor and threaten the universe with his manipulations and evil plans throughout the classic series. In the 1996 Doctor Who movie, actor Eric Roberts took on the role. When the BBC revived the show in 2005, the Master made a comeback, first as Derek Jacobi, and later as John Simm. However, the series surprised viewers with Michelle Gomez, who portrayed Missy, as the first female incarnation of the Master. This ultimately set up a story that made the first female Doctor possible, as currently portrayed by Jodie Whittaker.

Related: Doctor Who: How The New Master Compares To Previous Versions

In the latest episode of Doctor Who, Whittaker's Doctor travels the world on a grand spy mission only to discover that the Master has returned, this time as the mysterious "O," portrayed by Dhawan. The reveal of the Master's return in "Spyfall, Part 1" was a big one that surprised Doctor Who fans all over the world. However, in an official Doctor Who video, Dhawan breaks down the history of the Master, showing that the character is not one to stay down for long: he's always around.

The latest episode of Doctor Who not only brought the Master back. It also added some new ideas to the show's continuity. For starters, both UNIT and Torchwood get mentions as organizations that generally help Earth with alien threats. However, the episode revealed that both are now gone, leaving only MI-6 to deal with anything extraterrestrial that comes Earth's way. Season 12 is also the second season that did not have a Christmas special, instead choosing to air a Doctor Who episode on New Year's Day. This year, that episode is the first of the season, as well as the first of a two-part story that will continue on January 5. Showrunner Chris Chibnall seems to have big plans for season 12, including bringing back other classic Doctor Who villains, such as the Cybermen.

When it comes to classic Doctor Who villains, though, most fans would probably put the Master high on their list of favorites. It's yet to be seen if this latest incarnation will stick around for a while, or somehow get defeated in the next episode, but most would agree that his reappearance is a shocking, yet exciting, one.

Next: Doctor Who: Who Plays The New Master? Everything To Know About Sacha Dhawan

Source: Doctor Who/YouTube