What IS a Sonic Screwdriver?

Explore the mysteries behind the Doctor’s most beloved gadget...

Even if you'd only caught a single episode of Doctor Who, chances are you'd have spotted the compact device the Doctor frequently brandishes. This gizmo, known for its illuminating glow and distinctive whirring sound, has a knack for getting the Doctor extricated from all sorts of predicaments. But just what is this sonic screwdriver? What are its capabilities? Do we know its origin? And does anyone else in the universe possess one? Find out in this brief explainer of the Doctor’s favourite gadget.


The Sonic

What does it do?

The short answer is: it opens doors. The long answer is much more timey-wimey.

The Doctor tries their very best to be a pacifist, consistently seeking to resolve conflicts with words rather than weapons. So any device the Doctor employs is meant to assist, not harm. As the Tenth Doctor articulated, the sonic “doesn’t kill, doesn’t wound, doesn’t maim.” The sonic screwdriver is, on the other hand, very good at opening doors. Primarily used as a lockpicking device, the Sonic is renowned for allowing the Doctor and their companions access to places that they really shouldn’t be entering.
But it doesn’t end there! Despite being a small device with no visible interface, the Sonic has a zillion functions, operated by a psychic interface. Users merely need to point and think, and the Sonic will whir into action. Some of its uses include:

  • Scanning for alien tech
  • Disabling weapons
  • Detonating landmines
  • Boosting phone signals across time and space
  • Scanning medical information
  • Boosting X-rays
  • Writing (sometimes it’s a pen too!)

And let’s not forget its ability to reverse the polarity!

The Sonic is the ultimate multipurpose tool, enabling the Doctor to quickly join the fray and fend off threats. And, of course, it can also be quite helpful when assembling furniture.

So, how does it work?

As its name suggests, the sonic screwdriver operates on ultrasonic sound waves. It sends out vibrations to interact with the surrounding environment. That’s what the whirring sound is! How these vibrations actually perform half the functions the Sonic is known for, well, only a Time Lord could fully explain. Although other species have been seen using similar sonic probes, sonic screwdrivers are predominantly referred to as Gallifreyan technology. However, the Doctor, in defending their use of the Sonic, has hinted that they made their own: “Never had a lot of cabinets to put up?” It remains unclear if they were speaking specifically about their own Sonic or if they were implying that they were the inventor of the very first sonic screwdriver.

But why Sonic?

Again, sound waves! Also, the Doctor probably thinks it sounds cool, which it does.

When did it first appear?

The sonic screwdriver made its debut onscreen in the 1968 story, Fury from the Deep, where the Second Doctor, played by Patrick Troughton, uses it to… unscrew some screws! In its initial appearance, the Sonic looked more like a whistle. Images of this version are unfortunately scarce due to all six episodes being absent from the BBC Archives. Thankfully, Fury from the Deep was brought back to life through animation in 2020.

In this animated revivial, the sonic screwdriver was redesigned to look more like the version we see in future Second Doctor stories – a thin rod with a little light on the end. Since then, the sonic screwdriver has been a steadfast companion to almost all the Doctors, proving its worth time and time again!

What are its shortcomings?

A word of advice for any aspiring monsters out there: if you’re looking to prevent an adventurous Time Lord and their companion from breaching your base, bunker or spaceship, invest in some wooden doors! Yes, the sonic screwdriver’s biggest weakness is that it doesn’t function on wood. That is unless the user were to spend approximately 400 years calculating the exact harmonic resonance of said wood in order to dissolve it – but who has time for that (see The Day of the Doctor to find out!)? The Tenth Doctor also once mentioned that the Sonic doesn’t work in the presence of hairdryers. Hopefully, they've fixed that.

There have been occasions when the Doctor has been unfortunate enough to encounter monsters made of wood. However, he was once able to exploit the Sonic’s crucial design flaw to trick a wooden Cyberman into firing on itself!

The sonic screwdriver also fails to work on doors that are ‘deadlock sealed’ – but explaining those principles would take longer than a Time War!

Does the Doctor currently have one?

The Sonic was last seen in the final story starring the thirteenth incarnation of the Doctor, The Power of the Doctor. This particular Sonic was forged from Sheffield steel by the Doctor and accompanied the Thirteenth Doctor throughout their tenure. The Fourteenth Doctor briefly continued to use this Sonic, but it was destroyed by the Supreme Dalek in the Doctor Who Magazine comic, Liberation of the Daleks. However, a new sonic has recently been unveiled!

How many sonic screwdrivers are there?

It’s impossible to know exactly how many versions of the sonic screwdriver the Doctor has had over the course of their lives, especially considering that their narrative is perpetually evolving. However, at least 10 versions have been spotted on screen so far – and that's just those belonging to the Doctor. Each model has varied in design and size, but they all function in a similar manner.

Other characters from the Whoniverse have also brandished this ingenious device. River Song has her own model, an upgraded version of the one that the Tenth Doctor carried. There's also the Master’s laser screwdriver, Matron Cofelia’s sonic pen, Sarah Jane Smith’s sonic lipstick, and a whole array of sonic screwdriver-like gadgets used by the Doctor’s friends and foes. The Doctor even once referenced their laser spanner, though it’s anyone’s guess as to what that could be used for!

The Twelfth Doctor appeared to be nostalgic about previous Sonics, keeping them in a pen pot on their desk during their tenure lecturing at St. Luke’s.

Bill Potts and sonics

They even allowed their companion Nardole to use a version previously carried by the Fourth Doctor – perhaps because they didn’t trust him with a newer model! The Fifth and Sixth Doctors mostly opted to go ‘hands-free’ (the Sixth Doctor even had a sonic lance for a while), but by the era of the Time War, the Sonic was back in consistent use. While the Doctors often imprinted own unique flair on the design of the Sonic, each iteration used progressive versions of the same software, adding new features over the years.

So, that’s the sonic screwdriver! Despite being ineffectual on wood, its seemingly limitless functions and numerous designs make it a vital tool for the Doctor’s adventures and an iconic component of the Whoniverse.

If you think you've mastered your sonic screwdriver knowledge, why not put it to the test with our Savage Sonic Screwdriver quiz?

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