Professor Sarah Lasky was a thremmatologist who, along with Bruchner and Doland, developed a new species of plant called the Vervoids.
She met the Sixth Doctor and Melanie Bush aboard the Hyperion III in 2986. After her Vervoids began to hatch onboard, she tried to stop them from killing everyone on the ship, but was killed herself by a poison dart. (TV: Terror of the Vervoids)