The Master is a recurring and primary antagonist in the British science fiction television series Doctor Who. The character is a renegade Time Lord and was originally a childhood friend of the Doctor, both having studied at the Time Lord Academy on Gallifrey. The Master was driven insane after looking into the Untempered Schism, a portal to the time vortex, at the age of eight
. The Master is known for being a power-hungry "lover of chaos" and a universal conqueror who often seeks to control or dominate the universe. The character's distinctive ability includes hypnotizing people with an intense stare and commanding them with phrases like "I am the Master, and you will obey me"
. Since the character's introduction in 1971, the Master has been portrayed by multiple actors, with changes in appearance explained in the show's narrative as regenerations or body possessions, a biological trait of Time Lords. Notable actors include Roger Delgado, Anthony Ainley, John Simm, Michelle Gomez (as the female incarnation "Missy"), and Sacha Dhawan
. The Master has a complex history involving alliances with alien species such as the Daleks and Cybermen, and has been involved in major story arcs including the Time War. The character has been shown to survive death multiple times, often escaping seemingly fatal situations
. In recent storylines, the Master has taken on various forms and identities, including the female incarnation Missy, and has been involved in plots to conquer or destroy the universe. The Master’s relationship with the Doctor is marked by both rivalry and a deep, complicated connection stemming from their shared past
. In summary, the Master is the Doctor's arch-nemesis, a brilliant but malevolent Time Lord whose schemes and chaotic nature pose a constant threat to the Doctor and the universe
