The Twelfth Doctor’s era has received mixed reception fromDoctor Whofans. Some viewers point out the incredible episodes that aired during Series 8-10, including those starringbeloved villain Missy. Others, though, are dissatisfied with the inconsistency in the quality of the show’s writing. However, Peter Capaldi’s enthusiasm for the lead role carried the show through its weaker moments during this era.
Capaldi brought an intensity to the Doctor that few other actors have managed. Ten had his moments of awe-inspiring fury; Eleven struck fear into the hearts of enemies when he needed to — but Capaldi’s Twelfth Doctor had a zeal and passion that kept viewers glued to their screens. And there is no better example of how powerful his character could be than the Series 9 episode, “The Zygon Inversion.”

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The two-part story “The Zygon Invasion/The Zygon Inversion” calls back to the 50th Anniversary special. In that episode, the Tenth, Eleventh, and War Doctors negotiated a cease-fire between humans andthe shape-shifting alien raceof Zygons. It was eventually agreed that 20 million of the alien species would live peacefully on Earth, disguised as everyday humans. Now, however, the cease-fire has broken. A splinter group of Zygons have rebelled, deciding they are no longer content to live in hiding and want Earth for themselves. The Doctor must try desperately to stop a war while radical Zygons capture and kill humans, and Earth’s governments tighten their trigger fingers.

Bonnie, a Zygon impersonating Clara, goes in search of the Osgood Box, an item that is described as being able to end the cease-fire. Her aim is to unmask all Zygons on Earth, starting a war andtaking the planet by force— even though most Zygons are content to live in anonymity. But when she does find it, there are two boxes. And each box has two buttons inside.
Tensions culminate in a standoff between Kate Lethbridge-Stewart,head of UNIT, versus Bonnie. Each one stands in front of a box, hands hovering over two buttons, faced with a choice. One of Kate’s buttons will destroy every Zygon in the world; the other will blow up London. One of Bonnie’s buttons will reveal the true form of every Zygon; the other will keep all Zygons in human form forever.

And this is when, as he always does, the Doctor bursts in.
The Doctor has always believed in the power of speech over violence. He tries desperately to get Bonnie to see the flaws in her plan, the short-sighted nature of her revolution, the cycle of cruelty that she is perpetuating. He almost gets through to her, but a 50% chance of getting what she wants is enough for Bonnie — and from the opposite side of the table, Kate chimes in that it’s enough for her too. But the Doctor isn’t going to give up.
Modern incarnations of the Doctor havenever been fond of soldiers or military, having witnessed the Time War and the destruction that it brought. However, none have been so vocal about their disgust, frustration, and anger with the concept of war than Twelve — and this is where he has had enough. He describes the setup of the two sides, the two boxes, and the four buttons as “a scale model of war,” because war is always the same. The Doctor has seen countless bloody battles, seen countless innocents die in the crossfire, over the 2,000 years of his life. And before him now are two impulsive young creatures — hardly more than children compared to him. His impassioned speech to Kate and Bonnie, desperate to talk them both down from the ledge, isone of Capaldi’s best momentson the show:
“When you fire that first shot, no matter how right you feel, you have no idea who’s going to die! You don’t know whose children are going to scream and burn. How many hearts will be broken! How many lives shattered! How much blood will be spilled until everyone does what they were always going to have to from the very beginning: Sit down and talk!”
The Doctor has seen an untold amount of needless death and destruction, and in this moment he is desperate to prevent any more of it. He describes the pain he lives with, thepain of having done horrible things, and his determination not to let others feel it. Not only is he trying to protect the countless innocents of Earth — he’s trying to protect Kate and Bonnie too. That’s why, when Bonnie believes she’s gone too far to back down, he forgives her. As he says himself, it’s the only way to break the cycle. The Doctor’s words are both captivating and heartbreaking, and Peter Capaldi’s passionate performance makes it even more memorable.
Kate Lethbridge-Stewart is the first to close her box, after which Bonnie realizes that they are empty. There were never any weapons in the room; only tools to prevent death and destruction. Finallymoved by the Doctor’s wordsand beginning to understand his way of thinking, Bonnie backs down. By the end of the episode she has dedicated herself to protecting both the humans and Zygons that call Earth home.
Though he may not seem like it when he’s shouting at the top of his lungs, the Twelfth Doctor is ultimately a man of peace. He has seen enough war to last a lifetime, and knows that the consequences are always greater than anyone anticipates. His anti-war speech is one of his most powerful establishing character moments, and one that every Capaldi fan points to when naming him their favorite Doctor.
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