This article contains spoilers for the Doctor Who Centenary Special, The Power of the Doctor.Doctor Who finally honors the death of Adric (Matthew Waterhouse) after 40 long years. Doctor Who's centenary special, "The Power of the Doctor" sees the return of classic 1980s-era companions Tegan (Janet Fielding) and Ace (Sophie Aldred) to help the Thirteenth Doctor (Jodie Whittaker) battle against a terrifying triumvirate of the Master (Sacha Dhawan), the Daleks, and the Cybermen. Tegan has history with all three Doctor Who villains, but especially the Cybermen, who were responsible for the death of fellow TARDIS companion Adric. In Doctor Who's 1982 "Earthshock" serial, Adric sacrificed himself to prevent the Cybermen crashing a space freighter into Earth.

The following serial, "Time-Flight," saw the Fifth Doctor swiftly and coldly move on from Adric's Doctor Who death, causing tension with Tegan that never really disappeared. "The Power of the Doctor" finally confirms how greatly Adric's death impacted both characters. When Peter Davison's Fifth Doctor emerges to offer Tegan support as she attempts to blow up the Cybermen, he regains that lost trust by assuring her he never forgets any companion, then solemnly answers "Adric" when Tegan asks, "What am I thinking seeing all these Cybermen?" It's a touching moment that affirms the Doctor remembers Adric's sacrifice - despite never finding the right words before - and honors the companion's death 40 years on.

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Tegan Finally Gets Revenge On The Cybermen

Janet Fielding as Tegan and Sophie Aldred as Ace in Doctor Who

Although Tegan and the Doctor's grief over Adric has been explored through Doctor Who expanded media, those emotions hadn't been dealt with properly on-screen. 40 years after Adric's Doctor Who death, "The Power of the Doctor" finally lets Tegan avenge her friend when the Master dispatches a large Cyber-army, including Doctor Who season 12's Lone Cyberman, to U.N.I.T. headquarters. Tegan and Ace initially attempt to dispatch the Cyber-army using gold bullets, but the Cybermen proudly reveal they outgrew this weakness years ago. Interestingly, it was the gold in Adric's badge for mathematical excellence that the Doctor used to defeat Cybermen invading his TARDIS in the closing scenes of "Earthshock" - another sweet callback to the fallen companion.

With U.N.I.T. compromised, Kate Stewart (Jemma Redgrave) evacuates Tegan and Ace, but Tegan bravely stays behind to get her long-awaited Cybermen payback. Although she doesn't explicitly state it's a decision made out of revenge, there's something incredibly cathartic about the way Tegan saves the day, triggering a failsafe that detonates the whole of U.N.I.T.'s newly-leased building, burying the Cybermen beneath London. In doing so, Tegan narrowly saves Kate from cyber-conversion, and avenges Adric's Doctor Who death.

How Chris Chibnall Fixes A Fifth Doctor Mistake

Peter Davison as the Fifth Doctor in the Doctor Who centenary special and Adric's badge

With Jodie Whittaker's farewell episode, Chris Chibnall fixes Doctor Who's troubled 1980s, and honoring Adric is arguably the best example of that. The death of a companion was a rare occurrence in the classic era of Doctor Who, so writing Matthew Waterhouse's character out in such a brutal way represented a big deal at the time. Aside from some shocked expressions and a few companion pleas to go back in time, Doctor Who swiftly moved on. The Fifth Doctor's cameo and his emotional reunion with Tegan fixes the main issue with Adric's death - that nobody seemed to care.

Honoring Adric isn't the only way Chris Chibnall's final Doctor Who episode fixes the mistakes of the 1980s. By providing a fitting farewell between the Seventh Doctor (Sylvester McCoy) and Ace, and then including Mel (Bonnie Langford) in the Doctor Who support meeting scene, Chibnall puts a Doctor Who era that was previously unloved by the BBC at the very center of the corporation's centenary celebrations.

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