In the beginning of The Invasion Of Time, Leela storms off because the Doctor is being a dick. She eventually turns up in the pool, playing with an inflatable frog.
Later, a renegade Timelord helps the Sontarans break into the TARDIS, and they pursue the Doctor, Leela and Andred through lots of brick corridors and dingy workshops that look suspiciously like the BBC basement. Andred boldly holds them off with a pool chair (these are pretty inept Sontarans).
Later, there’s a sketchy-looking art gallery, a sketchier sick bay and a garden with a giant venus flytrap. Meanwhile, the Doctor’s Timelord mentor settles in by the pool, and manages to find himself a newspaper heralding the sinking of the Titanic, a blue beverage and a silly straw.