Window of Opportunity (Season 4, Episode 6) To be blunt, this episode is essentially SG-1's take on Groundhog Day, but that doesn't do Window of Opportunity justice.

Stargate SG-1 was in its eighth season when Black came aboard for a fun (and even funny) face-off against Dr. Daniel Jackson (Michael Shanks) as Vala Mal Doran in the episode “Prometheus Unbound ...