Clarissa MacDougall was part of the team that discovered the spacecraft Britannia. Upon boarding, her crew encountered Kimball Kinnison and Peter VanBuskirk, who initially mistook them for Boskonian enemies. She stayed aboard the Britannia while her crew attempted to repel attacking Boskonians. Though her crew failed, their effort gave her time to activate the vessel's inertialess drive, enabling an escape into hyperspace. This left her the sole survivor of her original team. She then took responsibility for ensuring Kimball Kinnison reached Admiral Haynes safely, explaining to him that the Lens was a link to Arisian consciousness.
During repairs on Delgon, she and VanBuskirk were captured. Kinnison led a rescue attempt that resulted in his severe injury. She provided medical aid to Kinnison during their subsequent escape, assisted by the alien Worsel of Velantia. The group fled to Radelix to evade danger.
Her background as a nurse came to the fore while she tended to Kinnison's injuries on Radelix. She insisted he rest to recover, but he disregarded her advice. Left alone, she was captured by Lord Helmuth. This capture forced Kinnison to confront Helmuth directly to secure her release.