Welcome to The Vault – jokingly known as 'The Museum of Terrors' – a high security establishment where UNIT keeps all of its alien artifacts.
New recruit Warrant Officer Charlie Sato is given a guided tour by Captain Ruth Matheson, and the archive reveals some dark secrets. An army jacket, a painting, crystal and a wax cylinder all hold a grave significance, and their stories are told by the Doctor's companions: Steven Taylor, Zoe Heriot, Jo Grant and Romana…
Tropes in Tales from the Vault include:
- Body Surf: Kali Korash is able to transfer his essence from one body to another when his current host dies.
- Chekhov's Armory: Each of the artefacts Ruth shows Charlie in their tour of the vault plays a part in the eventual defeat of Kali Korash.
- Clothes Make the Maniac: One of Jo's friends is possessed by a spirit inhabiting a Boer War army tunic he buys from a vintage shop.
- Evil Sounds Deep: When Charlie is possessed by Kali Korash, his voice drops about an octave and becomes far more resonant.
- Insult Backfire: After hearing Kali Korash's plan to lead the troops under his command into a massacre, Steven calls him 'psychotic'. Kali Korash takes this as a compliment.
- Landmarking the Hidden Base: The Vault is concealed under the Angel of the North
. - Laser-Guided Amnesia: The Second Doctor encounters a gang staging robberies and then using an alien crystal to wipe the minds of any witnesses so they cannot remember any details of the robbery. The Doctor eventually uses the crystal to wipe the gang leader's memory of the crystal and how to use it. Captain Matheson explains that UNIT Secret Ops now uses the crystal to remove memories of alien incursions and UNIT operations from people who are not amenable to other forms of coercion.
- Mythology Gag: Ruth reads out the details of Jo's audio cassette, but comments that the date is smudged: a reference to the UNIT dating controversy.
- Tomes of Prophecy and Fate: The Fourth Doctor identifies what has been incorrectly labelled an early impressionist painting as actually being an alien artefact that shows anyone who looks at it the circumstances of their death. The death cannot be changed or avoided, and anyone who looks at will go insane if they don't die first.
- Unspoken Plan Guarantee: Whatever the First Doctor's plan for defeating Kali Korash was, it obviously worked. However, the listener never gets to hear it because the wax cylinder is so deteriorated that the recording fades out before Steven can explain it.
- You're Insane!: Steven calls Kali Korash 'psychotic'. Kali Korash takes this as a compliment.
