Star Trek: Discovery fans have endlessly speculated on the identity of the Red Angel, and that has led to some great theories. The crimson apparition has been the central mystery of Star Trek: Discovery season 2; clues have been carefully dropped in the seven episodes that have aired thus far and have opened up some intriguing possibilities about who (and what) the Red Angel truly is.

Here's what we definitively know so far: the Red Angel is tied to seven red signals in space that appeared at the beginning of Star Trek: Discovery season 2. Captain Christopher Pike of the U.S.S. Enterprise took command of the Discovery and was charged with the mission to investigate the red signals, which have, in turn, led to three rescue missions mounted by the titular starship. In the first rescue, the Red Angel appeared before Michael Burnham. The second saw the Discovery save the planet Terralysium from an extinction-level event and the humans living there were transported to the Beta Quadrant by the Red Angel 200 years ago; it saved them from dying in World War III. Finally, the Red Angel directly interfered on a mission to First Officer Saru's homeworld of Kaminar; there, Saru confirmed that the mysterious being was a humanoid in a mechanized suit made of technology far beyond what Starfleet has in the 23rd century. The Red Angel also left behind trails of tachyon particles, indicating it's a time traveler.

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The Red Angel has also been afflicting Spock since he was a boy on Vulcan; it manifested to show Spock where to find his adopted sister Michael when she ran away from home. It's not only the source of Spock's nightmares but two months before season 2 began, the Red Angel appeared to Spock again. This crippled the Enterprise's Science Officer psychologically and allegedly led him to murder fellow Starfleet Officers to escape Starbase 5's psychiatric facility; Spock may be the only being who has answers to the Red Angel's identity and true intentions.

Until those answers arrive, fans merely have theories. While it's entirely possible the Red Angel could be revealed as someone brand new, just as tantalizing is the potential for it to be a Star Trek: Discovery character fans already know - or have heard of but haven't met yet. With that in mind, here are the five best theories about who the Red Angel could be:

Theory #1: The Red Angel Is Michael Burnham

Michael Burnham and Red Angel in Star Trek Discovery

Could the Red Angel actually be Michael Burnham, Star Trek: Discovery's main character? The two major possibilities here are that either the time traveling being is Michael from the future or the Michael from the Mirror Universe. If it's an older Michael who somehow acquired the means and tech to time travel, it would explain the Red Angel's focus on Spock (and on the current Michael who serves aboard the Discovery). While Michael isn't religious, having been raised by Sarek and Amanda Grayson on Vulcan, the Red Angel takes on a distinctly Earth-based Judeo-Christian form so it lends itself to the possibility that a human being is wearing the exosuit. The Red Angel also appeared before Michael when she was injured on an asteroid and later saved Saru's entire Kelpien race from extinction by the Ba'ul - this would make sense as something a future version of Michael would do, especially for Saru, whom she considers her family and is perhaps Star Trek: Discovery's best alien.

It's a more difficult argument to make that Mirror Universe Michael could be the Red Angel; the alternate version of Burnham was killed off in the tie-in comic Succession, which is considered canon unless Star Trek: Discovery's TV writers override it. What's more, Mirror Michael was a malevolent problem child of Emperor Philippa Georgiou who betrayed her mother and sided with her lover Gabriel Lorca to overthrow her. The Red Angel's apparent methods of leading the Discovery on rescue missions doesn't sound like something Mirror Michael would do, and that's not counting the logistics of how she would have gotten both to the future and to the Prime Universe to become the Red Angel. Still, nothing seems truly out of bounds for this series and it's quite possible the mysterious entity could be revealed as a doppelganger of Michael Burnham.

Related: Star Trek: Discovery's Kelpien Conflict References Multiple TOS Episodes

Theory #2: The Red Angel Is Spock From The Future

Leonard Nimoy as Spock and Star Trek Discovery's Red Angel

A fascinating possibility is the Red Angel could be the future version of Spock and strongly tie Star Trek: Discovery to the rebooted J.J. Abrams Star Trek films, which take place in the Kelvin timeline. How this would work would be to firmly establish Abrams' first Star Trek's pivotal timeline-altering film as canon for the CBS All-Access series by setting the destruction of Romulus as having definitively happened. In Abrams' film, the elder Spock in the 24th century tried to stop a supernova with red matter, but Romulus was destroyed and both Spock and a Romulan ship commanded by Nero were sucked into a black hole and deposited in the 23rd century, which created an alternate reality. In fact, the upcoming Jean-Luc Picard series starring Patrick Stewart is set after Romulus was destroyed.

If Spock is the Red Angel, it's possible his activities traveling through time could have occurred in between falling through the black hole and arriving in the 23rd century 25 years after Nero's appearance. Spock as the Red Angel makes a certain amount of sense as the Vulcan Ambassador could be using the Red Angel's future tech to "correct" problems in the past, especially involving his own family. After all, Spock has spent his extremely long life personally affecting the fate of the galaxy; as the Red Angel he could be both saving millions of lives and trying to heal rifts between himself, his adopted sister, and his parents.

Related: Star Trek: Discovery Corrects Season 1's Worst Moment

Theory #3: The Red Angel Is Zora, The Discovery's Future A.I.

Star Trek Discovery Red Angel AI

It's also possible that, rather than a flesh-and-blood person, the Red Angel could be Zora, the Discovery's A.I. from a thousand years in the future. The Short Trek episode "Calypso" established that the Starship Discovery survives into the 33rd century, adrift in an unknown region of space having long-since been abandoned by her crew. The ship's computer evolved itself and became sentient, calling itself Zora. In "Calypso", Zora saved a human named Craft who was lost in an escape pod; after nursing him back to health, they had a bit of a romance before Craft chose to return to his world, Alcor IV, to reunite with his family.

The Red Angel could conceivably be Zora's next stage in her own evolution; the Discovery's A.I. possesses 100,000 years of galactic history it gained from a dying sphere in the episode "An Obol for Charon", which could include the secret of time travel. With her millennia-advanced tech, Zora could then have replicated the humanoid form of the Red Angel to begin altering the Discovery's own past - possibly to prevent Zora's lonely 33rd-century existence. If this turns out to be the case, it would be a fitting and very Star Trek-worthy story as a season-long sequel to "Calypso", which would then make the Short Treks essential viewing for fans.

Page 2 of 2: The Red Angel Could Be Characters Star Trek: Discovery Hasn't Introduced

Theory #4: The Red Angel Is Gabriel Lorca

The Red Angel could turn out to be Gabriel Lorca, marking the return of Star Trek: Discovery's season 1 "big bad" - or possibly his unseen Prime Universe counterpart. Fans have never met the 'original' Lorca since it was his Mirror Universe duplicate who was masquerading as Captain of the Discovery in season 1.  Thanks to Michael Burnham, Lorca's scheme to overthrow the Mirror Universe's Emperor Georgiou failed, but the duplicitous ex-captain may have survived both being run through by Georgiou's sword and falling into the Imperial flagship's mycelial reactor. It would make sense if Lorca were the Red Angel; the mycelial network could have transported him to the future and, armed with advanced tech, Lorca is megalomaniacal enough to meddle in the past and threaten the galaxy. Lorca's obsession with Michael Burnham could also explain why the Red Angel has been tormenting Spock for years.

However, the Red Angel could also be an opportunity to debut Prime Universe Lorca - a character fans have only heard about. Although shock value aside, there's little concrete evidence to suggest Prime Lorca could be the time traveling being. According to the tie-in novel Drastic Measures, Prime Lorca could still be alive in the Mirror Universe, but it would require a lot of storytelling logistics to explain how he could possibly become the Red Angel from the future affecting the Prime Universe. Still, it remains difficult to believe that fans have truly seen the last of Jason Isaacs on Star Trek: Discovery and either version of Gabriel Lorca appearing would indeed make for a stunning turn of events.

Related: Star Trek Shorts Secretly Reveal Discovery's Season 2 Story

Theory #5: The Red Angel Is The Real Ash Tyler

Star Trek Discovery Ash Tyler Section 31

The Red Angel could be revealed as another character fans have heard about but never met - the real Ash Tyler. The man who was Torchbearer to Klingon High Chancellor L'Rell and is now an agent of Section 31 is Voq, which was surgically altered into Ash Tyler, with his human personality laid on top of the Klingon's. Yet, the whereabouts of the true Tyler have not been revealed; all fans know is Ash was a Starfleet Lieutenant who was captured by the Klingons during the Battle at the Binary Stars during season 1. Whether or not the man Voq took the form of is even still alive is unclear.

Like Prime Universe Lorca, the real Ash Tyler taking the identity of the time-traveling Red Angel would require a great deal of explanation, and the main draw of this theory is simply explaining what happened to this unseen character. The real Ash has never met anyone on the Discovery, as far as fans are aware, and there's no known reason he would target Spock. However, if the Red Angel is the true Ash Tyler who somehow traveled to the future, he could conceivably have access to the knowledge his counterpart in Section 31 has - and he could be seeking to undo the damage Starfleet's secret agency is doing clandestinely. This would be another mind-bending twist, but those are becoming par for the course on Star Trek: Discovery.

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Star Trek: Discovery streams Thursdays @ 8:30pm on CBS All-Access and internationally the next day on Netflix.