(written from a Production point of view)
Gregory got his start acting in the teen ghost comedy The Heavenly Kid(1985) with VOY guest Mark Metcalf which remains to this day as Gregory's sole film work. Gregory then found himself only working in guest roles. The first was on the medical drama St. Elsewhere starring Ed Begley, Jr., Bruce Greenwood, and Norman Lloyd in "Getting Ahead" (1987) followed by the teen crime drama 21 Jump Street in the interestingly titled "Next Generation" with fellow TNG guest Michael Ensign. Gregory's last single guest appearance was on the short-lived Houston Knghts in "Bad Paper" with Nicholas Worth.
Gregory's most stable television work as well as an actor outright is the recurring role as Dr. Kyle Beresford on the Law & Order spin-off Special Victims Unit. Working in the seventh season "Raw" (2005) with John Rubinstein, "Starved" (also 2005) with Teri Garr, "Storm" with John Schuck, "Alien" with Amy Pietz, and in 2006, first in "Blast" with Kaitlin Hopkins and then in that season's finale "Influence" with Jeff McCarthy. Gregory portrayed Beresford before and after these episodes but only these had Gregory working with other Trek actors.