Warning: the following contains SPOILERS for Star Trek: Picard.
Star Trek history within the Prime Universe itself. Although Q's appearance in Star Trek: Picard season 2, episode 1 “The Star Gazer” is a surprise, the series has been reintroducing fans to many of the classic characters from the franchise since season 1. Even though very little is known about the Watcher, it's likely to be someone from Picard's past.
In Star Trek: Picard season 2, the crew find themselves trapped in an alternate Earth ruled by the fascist and xenophobic Confederation of Earth instead of the United Federation of Planets. Despite this, Q has preserved the Prime Universe memories of Picard and his crew, which now includes the Borg Queen (Annie Wersching) herself. In a strange development that could forever change the future and evolution of Star Trek's Borg in the Prime Universe, the Borg Queen is recruited into Picard's motley crew, functioning both as the crew's chief computer scientist and mad alien prophet. Thanks to the Borg Queen's cross-temporal awareness, she deduces that Q's changes to the Prime Universe are rooted in a single temporal recession in Los Angeles in the year 2024. The Borg Queen also tells Picard that Q was not alone – “There is someone there to help, a Watcher. Seek the Watcher.”
Star Trek: Picard provides several clues regarding the Watcher's true identity. While Q is being his usual vague self, his pronouncements indicate that he wants Picard to find forgiveness or penance, and that this fascist world was birthed through human decisions. Based on these factors, someone from Picard's past will soon the Star Trek: Picard season 2's time travel conundrum.
Another likely candidate for the role of Q's Watcher is the El-Aurian Guinan (Whoopi Goldberg), who returned to the franchise in Star Trek: Picard season 2. El-Aurians are known for being a race of listeners due to their inherent patience and wisdom. They also live for around 700 years, which means that Guinan was alive in 2024. Seeking romantic advice after his awkward encounter with the Vulcan Laris (Orla Brady), Picard shares a bottle of Cerulean brandy with Guinan, who accurately psychoanalyzes Picard's fear of love and commitment. According to Guinan, Picard is being held back romantically by an internal issue or conflict that he is yet to resolve. It wouldn't be beyond Guinan to temporarily ally herself with Q as the Watcher in order to give Picard one final test that would help him to finally come to with his past. Indeed, Jean Luc Picard's backstory and childhood trauma might be the only true frontiers remaining for the intrepid galactic explorer.
Star Trek: Picard continues the beloved franchise's tradition of using sci-fi to unravel the human condition through groundbreaking storytelling. Whoever the Watcher is, they are bound to play a huge role in how Picard's crew can resolve Q's twisted new test. While it would make sense for either Adam Soong or Guinan to be working with Q, any one of the other classic Star Trek characters could be revealed as Q's Watcher.
Star Trek: Picard Season 2 streams Thursdays on Paramount+.