FyreLyn joined the Leviathan-A as the junior medical officer just before if left Deep Space 9 to engage the Bariens. Having previous served at Starfleet Medical for three years after graduating, she made the request to join a Starfleet vessel in the hope of finding a more adventurous life.

A junior grade Lieutenant at the time, she 'inherited' the role of Chief Medical Officer when the current doctor was killed during a Barien attack. Forced to take over, she performed outstanding work in sickbay, a fact that Captain Devore recognised by promoting her to the rank of full Lieutenant.