Emory Erickson's son, trapped in subspace for fifteen years after an early transporter experiment went wrong.
Quinn Erickson is the son of the transporter's inventor, Emory Erickson. Fifteen years before Daedalus, he vanished during an early transporter experiment, and his father has spent the years since trying to find a way to bring him back.
In Daedalus his presence aboard Enterprise appears as a mysterious photonic ghost, and T'Pol's scans reveal his identity. Emory's efforts to retrieve him lead to the death of a crewman and leave Archer to judge how far a grieving father may go.