Star Trek: 10 Times Aliens Influenced Human History

The supervisors are highly skilled agents, directed by powerful, time-travelling beings. These "travellers" use the supervisors to "watch over the grand tapestry of history." Their true end-goal is still mysterious, but they step in only at key moments, usually to protect others when all other options fail.

The Original Series episode Assignment: Earth first introduced us to a supervisor, the Human Gary Seven, who worked to prevent a nuclear apocalypse on Earth in 1968.

Decades later, we saw a second supervisor in Star Trek: Picard: the Romulan Tallinn, who was tasked with protecting René Picard, an extremely important historical figure related to Jean-Luc Picard. It wasn't until the second season finale, Farewell, that we learned that the supervisors were actually controlled by the Travellers, who Wesley Crusher left with to explore space and time in the Next Generation episode Journey's End.

So far, Gary Seven, Tallinn, and Kore Soong (who Wesley recruited in Farewell) are the only supervisors we've seen in Trek, but it's reasonable to assume that there are many more working on Earth and other planets all throughout history. The scene with Wesley from Picard really seemed like it was setting up something more with his and Kore's characters, so we're probably going to learn more about these agents soon.