Salem's Inner Circle is a faction that consists of Salem and her subordinates. Their objective is unclear, but apparently involves changing the world of Remnant through the use of the four Relics and the destruction of the Academies which each house one of the Relics. They also appear to be hunting down and taking the powers of the four Maidens, as their powers are the keys to unlocking the vaults holding the Relics. The group is closely connected to the Creatures of Grimm, as their headquarters is located in the Land of Darkness.
The origins of the group are not clear, but it is shown to have existed for generations. Decades before the start of the series, Salem had taken Tock as a subordinate to hunt down Silver-Eyed Warriors. Salem served as a mentor to Tock, advising her on how to properly use her Semblance despite her follower not taking heed, ultimately leading to her demise at the hands of Maria Calavera.
In recent history, Cinder Fall and the other members were presumably brought into the fold by Salem to assist in her plans. The activities of Cinder and her group, including the recruitment of Adam Taurus and the White Fang, the theft of the Fall Maiden's powers and the destruction of Beacon Academy, were carried out under Salem's direction. Cinder's status as the Fall Maiden is described by Salem as being "key" to their further moves. However, due to Cinder's new unspecified "weakness", Salem instead opts to keep Cinder close to her.
The actions of the other members are not known in detail. Tyrian has been on the hunt for the Spring Maiden for some time, though at a meeting following the Fall of Beacon, he is reassigned to capture and retrieve Ruby Rose after she defeated Cinder. At the same meeting, Watts is assigned to carry out Cinder's role in meeting with Professor Lionheart in Mistral. Hazel is to attend a meeting arranged by Adam with the leader of the White Fang, Sienna Khan, in order to bring her to heel.
Tyrian fails to defeat Ruby due to the intervention of Qrow Branwen and loses his tail in the process, but Watts' meeting with Professor Lionheart goes well and leads to Lionheart's complete obedience with Salem's plans. Additionally, Hazel's meeting with Sienna leads to Adam killing her and taking over the White Fang, much to Hazel's discontent.
Hazel and Tyrian killed a majority of professional huntsmen in Mistral whose identities were supplied by Leonheart after he allied himself with Salem. Qrow found out after trying to gather allies for their battle against Salem.
Following Beacon, Haven Academy is their next target. Lionheart, Cinder's Faction and Hazel, with aid from Raven Branwen, Vernal and Adam's White Fang troops, plan to enter Haven Academy's Vault to retrieve the Relic of Knowledge and destroy the CCT when they are finished to make their escape.
However, the attack proves to be a failure: Cinder is defeated by Raven in the Vault, while Emerald, Mercury, and Hazel are forced to retreat, Lionheart flees the battle and is killed shortly after by Salem, and the White Fang are stopped by the combined forces of the Menagerie Faunus and the Mistral Police, with only Adam escaping capture. Ozpin's forces retrieve the Relic and plan to take it to Atlas.
Other notable associates of the group include Cinder Fall's underlings, Emerald Sustrai and Mercury Black, as well as Adam Taurus of the White Fang. They also had an informant in Mistral, who is revealed to be Professor Lionheart, the Headmaster of Haven Academy, but Salem kills him for his cowardice during the Battle of Haven.
Although not an official name, composer Alex Abraham named the theme that plays when Salem walks into the meeting room in "The Next Step", "A Dark Cabal", most likely referring to Salem's Inner Circle. The group has also been referred to as Salem's Court and Team WTCH (Witch).
The allusion theme of Salem's followers takes well-known "hero" characters and changes their stories to make them turn into villains.