Although many fans of Doctor Who hated the 12th Doctor’s sonic sunglasses when they were introduced in season 9, their masterful use in season 10 made up for it. The Doctor first uses the new gadget in “The Witch’s Familiar,” surprising both Clara and everyone watching the episode. While the sunglasses allow Clara and the Doctor to narrowly escape the Daleks, they weren’t popular among fans of the show. Most fans saw no reason for the Doctor to abandon his iconic sonic screwdriver for the sunglasses, which felt like a whimsical gimmick designed for younger audiences

The problem with the sonic sunglasses in season 9 is that the Doctor has no real reason to use them instead of a much more practical screwdriver. They have no difference from a sonic screwdriver other than simply being shaped like sunglasses. Season 10 solves this issue by placing the Doctor in situations where sunglasses specifically would be advantageous over a screwdriver, finally transforming the new device into a compelling part of the plot instead of just a toy. One of the most defining moments of Doctor Who season 10 is when the Doctor goes blind in “Oxygen.” Not only is this an interesting narrative choice, but the Doctor suddenly has a real reason to use the sonic sunglasses. In “Extremis,” the Doctor decides not to tell anyone that he’s gone blind, a choice only made possible because the sonic sunglasses provide a rough digital rendering of his surroundings. Suddenly, the sonic sunglasses are not only relevant, but they’re the most crucial part of the show.

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The shining moment of the sonic sunglasses, however, doesn’t come until the very end of “Extremis.” In the last few minutes of the episode, the Doctor realizes he’s inside a simulation designed to provide the Monks with a training ground for taking over the earth. In learning this, the Doctor also learns he isn’t even the real Doctor; he’s a digital rendering who is powerless against the Monks outside of the simulation. But in a moment of classic Doctor brilliance, he realizes that while he can’t save the outside world, there’s someone who can: the Doctor! Lucky for him, his blindness means that he’s been wearing the sunglasses for the entire episode. The sonic sunglasses were recording the whole time, meaning the simulated Doctor is able to send the real Doctor footage of everything that happened in the virtual world. Here, the audience learns that the entire episode was the real Doctor watching the footage he received from the simulated Doctor.

Doctor Who sonic sunglasses

Doctor Who season 10 uses the sonic sunglasses masterfully for two reasons. Firstly, they allow the Doctor to keep his blindness a secret, creating dramatic irony that infuses the episode with tension and suspense. Watching the Doctor navigate his surroundings in almost total darkness provides a certain uniqueness, in addition to urgent source of conflict. Secondly, the twist at the end of “Extremis” is so clever that it makes up for basically every whimsical use of the sunglasses in season 9.

Even though the sonic sunglasses redeemed themselves after their rocky start in season 9, Doctor Who has since reverted to the screwdriver. But notably, the 13th Doctor’s sonic screwdriver is more unique than those of her previous incarnations; it’s the only one she builds herself, fashioned from some spoons and other loose pieces of scrap metal. So while the sonic sunglasses were the first non-screwdriver sonic device the Doctor regularly carried, maybe they were a trailblazer for some more unique sonic gadgets.

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