They are typically modelled after the fictional character Abraham Van Helsing from Bram Stoker's novel Dracula.

Watchers are devoted to tracking and fighting malevolent supernatural entities, particularly vampires, primarily by locating individuals with the talents required to combat such beings and emerge victorious.

More specifically, Watchers are assigned to Slayers, girls who are part of a succession of mystically powered individuals destined to confront these foes.

After being fired by the Council for having "a father's love" for the Slayer in season 3, he remained her unofficial Watcher for the rest of the series.

Watchers are typically well versed in hand-to-hand combat techniques, though they generally confine themselves to training Slayers or supporting them in battles, as their lower strength relatively limits their effectiveness in directly engaging vampires.

He shows her a vision of the First's army of Turok-Han in the Hellmouth, causing her to start to reconsider her decision, but she is brought back by her friends before she can do anything else.

Over the years, however, the Council has become increasingly arrogant and egocentric, believing themselves to be the supreme authority while the Slayers are just their tools.

[4] In the aftermath of the battle with the army of The First and the destruction of the Sunnydale Hellmouth, the Watchers' Council begins the process of rebuilding.

[5] The structure of this new Council is unknown, but it appears that Rupert Giles is its new head and is training Andrew Wells as a Watcher.

In the canonical comic Buffy the Vampire Slayer Season Eight, Giles informs Faith that he is, for all intents and purposes, the Watcher's Council.

When Faith Lehane stakes and kills a human, the Special Ops Team was dispatched to retrieve the rogue Slayer, circumventing local and international authorities.

When one particular Watcher, Rupert Giles, defies the rules of the test and interferes in the Cruciamentum of his Slayer – Buffy Summers – he is dismissed from his position immediately.

[11] In 2001, representatives of the Council visit Sunnydale, California to deliver vital information on the seemingly unstoppable Glory to the Slayer, Buffy Summers.

She defends the frequent assistance of her friends (Slayers typically operate alone) and demands that Rupert Giles be reinstated as her Watcher, with retroactive pay to the time of his dismissal.

They remain in hiding until Buffy Summers discovers the Scythe and tracks its origin to an Egyptian-style tomb, where the last Guardian waits.

The (non-canon) novels and comics, especially those focusing on previous Slayers, show or mention other Watchers including: Michaela Tomassi (The Gatekeeper trilogy), Archibald Lassiter (Giles), Harold and John Travers (Pretty Maids All in a Row), Yanna Narvik (watched over the Slayer, Sophie Carstensen in Pretty Maids All in a Row), Marie-Christine Fontaine (watched Slayer, Eleanor Boudreau in Pretty Maids All in a Row), Diana Dormer (the name given to Faith's first Watcher in Go Ask Malice).

J'annine Jobling believes that there is a parallel between the Watcher's Council and religious organizations, because they are "bound by tradition and hierarchy", while Buffy and her friends act more democratically and are motivated by love.