Editor's Note: The following contains spoilers for Star Trek: Picard Season 2.Star Trek: Picard has pulled off an impressive feat not just once, but twice, by keeping a huge spoiler under wraps. First, the show was able to keep the Season 3 The Next Generation reunion a secret, announcing the massive event on their own schedule. The show also was able to keep Wil Wheaton's Wesley Crusher/Traveler hush-hush, surprising viewers upon his appearance in the Season 2 finale, "Farewell." This is an even more impressive achievement, considering fans' understandably upset reaction to the Season 3 announcement when Wheaton's name wasn't included. But with his last major appearance in the Star Trek universe happening some 28 years ago, audiences may struggle to remember exactly how he got into this position, and exactly what he is. Some Star Trek fans weren't even alive in 1994. (I wasn't!)
Supervisors
Gary Seven (Robert Lansing) was the first supervisor seen in the Star Trek universe, appearing in the 1968 Star Trek: The Original Series episode, "Assignment: Earth." When the USS Enterprise moves back in time to conduct historical research, they intercept Seven beaming onto Earth. Gary's mission is to prevent a nuclear missile launch. He is successful by the end of the episode and remains in place on Earth for future missions that will help keep the flow of time intact. Although Seven only appears in one episode in The Original Series, this would be the main piece of lore that Wesley's Traveler arc would rely on.
Supervisors, themselves, aren't seen again in Star Trek until Picard when Tallinn (Orla Brady) is introduced as an ancestor to the already-featured Laris, also portrayed by Brady. Her mission is to watch over and protect Renee Picard so she may make the discovery on the 2024 Europa Mission of a microorganism capable of helping solve climate change. Whereas Seven was taken by the Travelers millennium before the present day, Tallinn is a disguised Romulan working on Earth. The two agents show that Supervisors can have a multitude of missions, from preventing violence to protecting influential lives. This is the role that Crusher recruits Kore (Isa Briones) to in his surprise appearance on "Farewell."
The Traveler
Travelers weren't introduced until a 3-episode series-spanning arc on The Next Generation. The Traveler (Eric Menyuk) first appeared in the Season 1 episode, "Where No One has Gone Before." The Traveler possesses a swath of abilities, many of which can alter reality, time, and space. To study humanity, they used their abilities to act as a Starfleet propulsion expert's assistant, the secret driving force behind the propulsion expert's new revolutionary theory. While on the Enterprise, The Traveler accidentally sends them to a new galaxy, to the end of the universe, and back to the Milky Way. They notice Wesley while onboard, secretly prompting Picard (Patrick Stewart) to promote Wesley to an acting ensign, ultimately already helping to shape Wesley's life.
The second time The Traveler appears is in the Season 4 episode, "Remember Me." Wesley, having matured and begun developing his Traveler abilities, accidentally traps his mother, Beverly Crusher (Gates McFadden), in a warp bubble during an experiment, leaving her trapped in a parallel reality. The abilities draw The Traveler back to the Enterprise when they sense the situation and are able to help return her to safety but to do so, he has to convince Wesley of his own ability.
Season 7 Episode 20, "Journey's End" not only marks The Traveler's last appearance, but also Wesley's last appearance until his brief cameo in Star Trek: Nemesis, even briefer than his scene in Picard, as most of his appearance was cut from the scene that made it to the movie. In this episode, The Traveler appears incognito as a villager to Crusher, leading him to experience a vision of his father. He advises Wesley, who was already unsure of his Starfleet future, to follow his true journey outside Starfleet. Listening to the advice, Wesley resigns. Later, during a riot on a planet, he disassociates from time and The Traveler reveals their true form, for Wesley is ready to begin his new journey.
Wesley's Future
The younger Crusher's cameo doesn't just further solidify the connection between the Travelers and their chosen Supervisors, but it also cleans up the very different The Next Generation ending for Wesley and his appearance at Deanna Troi (Marina Sirtis) and William Riker's (Jonathan Frakes) wedding in Nemesis. While he attends the ceremony in Starfleet uniform, it's likely that this is just an appearance he projects as The Traveler did similarly in "Journey's End." From Wesley's comedic exposition in his recruitment speech to Kore, it's clear that he has spent plenty of time traveling and maintaining the flow of time. While his days as Wesley Crusher are far behind him, this new Traveler can still recall back to his days as the young Ensign on the USS Enterprise and use the totality of his experiences to bring other lost souls into the fold.