Captain of the U.S.S. Olympia, Cusak was born in 2323 and died 2371. In 2363, Cusak commanded the Olympia on an eight-year mission of long-range exploration in the Beta Quadrant. On its return to Federation space in 2371, Cusak's ship stopped to investigate a Class-L planet in the Rutharian sector, where active sensor scans triggered a quantum reaction in an exogenic energy field surrounding the planet.

This reaction caused a surge of metreon radiation, which destroyed the ship. Captain Cusak's escape pod landed on the surface of the planet, where she survived for several days in a cave, extending her life with triox injections before succumbing to carbon dioxide poisoning. Prior to her death, she called for help using subspace radio, but the signal was distorted through the planet's exogenic field, and was time-shifted three years into her future.

In 2374, the U.S.S. Defiant picked up Cusak's, unaware of the time-shift, and set out on a rescue mission. The Defiant crew was able to talk to Cusak and got to know her — and she them — quite well. But when the Defiant arrived, her three-year-old corpse was discovered. The crew brought her body back to Deep Space Nine for an Irish wake, where she was toasted by her new friends.