Sonic umbrella
From Tardis Wiki, the free Doctor Who reference
A sonic umbrella was a device used by Missy aboard a Mondasian colony ship. The activation controls where located at the handle end opposite the emitter at the tip. Missy used her umbrella to locate and call up a lift onboard the Mondasian colony ship. (TV: World Enough and Time/The Doctor Falls)
Behind the Scenes
It is unknown if the sonic umbrella used by Missy in World Enough and Time is the same umbrella that she had in Deep Breath, Dark Water and Death in Heaven.
