The return of a classic Doctor Who companion has become necessary after season 14’s big Pantheon retcon. From Sutekh piggybacking on the TARDIS to the reintroduction of Richard E. Grant’s Shalka Doctor, there was no shortage of canon rewrites in Doctor Who season 14. While Sutekh’s 49-year reign as hide-and-seek champion was undoubtedly the biggest retcon, the most significant change for future storylines proved to be the formation of Doctor Who‘s Pantheon – an order of immortal, near-omnipotent godlike entities presiding over time and space.

Sutekh sits atop the Pantheon as its God of Death, while Doctor Who has also confirmed the Toymaker as the God of Games and Jinkx Monsoon’s Maestro as the God of Music. The names of several previously-unmentioned deities have also been dropped, and it’s possible that more classic Doctor Who villains besides Sutekh and the Toymaker will be redefined as members of Doctor Who‘s Pantheon in future episodes. One particular Pantheon detail, however, demands a former companion return in Doctor Who season 15.

Doctor Who Season 14 Confirms The Mara Is A Member Of The Pantheon

The Mara Seems Far More Important After Doctor Who Season 14

Doctor Who season 14 officially proclaimed the Mara as the Pantheon’s God of Beasts. This snake-like villain debuted during the Fifth Doctor episode “Kinda” and quickly possessed then-companion Tegan Jovanka, played by Janet Fielding. The Doctor believed he had purged the Mara from Tegan, but the following season’s “Snakedance” proved otherwise, revealing she had been carrying the creature in her mind. Once again, “Snakedance” ended with the Doctor believing Tegan had been freed and the Mara was defeated. The villain has not been glimpsed in Doctor Who TV continuity since.

Before Doctor Who season 14, the Mara was a powerful, animalistic alien force – a psychic snake spirit hailing from the planet Manussa. Unconventional, hard-to-define, and ethereal the Mara may have been, but classic Doctor Who offered no suggestion of the Mara’s Pantheon status. Knowing the truth casts “Kinda” and “Snakedance” in a very different light. Tegan didn’t just get bitten by some exotic creature while traveling to a distant world – a member of Doctor Who‘s Pantheon inhabited her body for an entire season. In the context of season 14’s canon changes, the Mara possessing Tegan becomes way more significant.

Sutekh can turn the dead into his heralds, and the Toymaker can manipulate mortals like puppets, but only the Mara has mentally merged with a Doctor Who companion for an extended period of time. The snake and Sutekh were probably snickering at each other from opposite ends of the TARDIS as the Fifth Doctor unknowingly gave both Pantheon Gods a free ride. Tegan’s experience with the Mara feels far more menacing with the benefit of hindsight, and Doctor Who can now revisit her possession from a post-Sutekh angle.

Doctor Who Previously Hinted That Tegan Is Still Possessed By The Mara

Is The Mara Still Inside Tegan? Doctor Who Thinks So

Since the Mara is actually a Pantheon God, the Fifth Doctor probably didn’t defeat it at the end of “Snakedance.” The Mara eluded the Fifth Doctor once after surviving in “Kinda,” just like the Fourth Doctor presuming Sutekh had been bested in “Pyramids of Mars,” and these instances clearly demonstrate the Doctor’s unfortunate habit of being tricked into thinking Pantheon villains are dead. After Sutekh spent millennia hiding inside the TARDIS without detection, the Mara surviving within Tegan doesn’t just seem plausible – it feels inevitable.

Indeed, Doctor Who‘s modern era has explicitly set up the Mara’s lingering connection to Tegan via its wider releases. “The Passenger,” a short film made for Doctor Who season 20’s home media release and starring Janet Fielding as the returning Tegan, confirmed that the Mara remains embedded into the ex-companion’s consciousness.

Part of Doctor Who‘s well-regarded Collection shorts, the canon status of “The Passenger” is up for debate. On one hand, Doctor Who showrunner Russell T Davies is unlikely to ever let the Collection films restrict his TV show. On the other, Doctor Who‘s “Collection” shorts are designed to complement canon, and “The Passenger” lines up neatly with the franchise’s past. Doctor Who season 15 could easily follow up “The Passenger” by reintroducing Tegan possessed by the Mara, and doing so would feel even more appropriate after the reptilian menace was retconned into the Pantheon.

Tegan’s Last Doctor Who Appearance Makes Her Return Even More Crucial

Is Tegan A Danger To UNIT?

Janet Fielding returning as Tegan in Doctor Who season 15 becomes even more pressing when taking her most recent canon appearance into account. Tegan last featured in Jodie Whittaker episode “The Power of the Doctor” as a UNIT recruit alongside fellow former companion Ace. “The Power of the Doctor” aired prior to “The Passenger” and long before the Mara was bestowed Pantheon God status, and it was assumed throughout the episode that Tegan was still Mara-free.

If, however, Tegan was still carrying the Mara in her subconscious – as suggested by “The Passenger” and then further supported by season 14’s retcon – then a Pantheon villain has been enjoying full access to UNIT’s resources. Sutekh may have slipped one of his harbingers into UNIT headquarters, but the Mara secretly taking advantage of the organization’s data and technology through Tegan is a far bigger problem. As UNIT continues to appear in Doctor Who season 15 and beyond, addressing Tegan’s status as a cosmic security risk feels unavoidable.