Synopsis: When the Doctor and Sarah land on Vortis, they discover that the butterfly-like Menoptrans are once again in trouble. Plagued by unusual energy emissions on a remote part of the planety, they've sent a scientific party to investigate. Unfortunately, they've all been killed.
The only survivor, a wingless Menoptran named Jresta, can't quite piece together what happened.
As she and the Doctor are talking, a new scientific team arrives, led by the more authoritarian Vursus. He plunges forward, back towards the source of the emissions. As his team, Jresta and the TARDIS team explore, they discover that the emissions are coming from an odd crystal. Ignoring warnings to leave it be, Vursus orders a sample of the crystal be taken. When a piece is broken off, the emissions go off the charts and the Menoptrans are mesmerized. They all fly into the greater energy "web" that results. The Doctor activates his sonic screwdriver to a resonant frequency, and the crystal is destroyed.
Sarah and the Doctor depart Vortis, leaving Jresta, spared from the attack because she can't fly, to explain to her people what has happened.
Synopsis: The Fifth Doctor returns to Gallifrey. A Time Lord has been killed, and he must figure out why. Tegan has a cold, so she remains in the TARDIS, making Nyssa to go-to companion for this story.
On Gallifrey, the duo discover that a small sect of Time Lords believe Rasilon, the most famous and influential Time Lord of them all, was a vampire. So frenzied are they in their belief, that one of them has actually injected himself with vampiric DNA.
Nyssa and the Doctor frantically search the Capitol for vampire DNA. They find him, however, too late. He has gone to the Doctor's TARDIS and bitten the ailing Tegan. Now in control of the Doctor's TARDIS, he intends to go to Earth to "infect' a bunch of humans, so he can have an invasion army to take back to Gallifrey. Focused only on the Doctor, the vampire-Time Lord doesn't suspect that the girls have any knowledge of TARDIS operation. Nyssa, though, has slyly altered the TARDIS landing protocols. The TARDIS doors open on earth to brilliant sunlight, foiling the vampire's plan to land in the dead of night. He crumbles to dust, and Tegan is returned to nomral.
Notes: Probably a sequel for the author's novel, Goth Opera.