Box (The Playthings of Fo)
A black box was a device which the First Doctor kept in a storeroom in the TARDIS.
On Rhoos, the Doctor was captured by Fo and taken to his lair, but he made his way to the TARDIS and got a black box from the storeroom. He placed the box on the ground, opened the box and threw himself to the ground. The box let out a flash of blue light, the smell of ozone filled the air, and Fo fell down dead. (PROSE: The Playthings of Fo [+]Loading...["The Playthings of Fo (short story)"])
Behind the scenes[[edit] | [edit source]]
It is not made clear exactly what the box did to kill Fo; however, the reference to blue light and the smell of ozone would seem to imply that it emitted an electrical charge powerful enough to slay the giant.