Star trek The Complete Fourth Season (DVD)
Following the season-long Xindi arc during the third season, season four comprised several shorter story arcs. These included a wrap-up to the Temporal Cold War storyline which began with the pilot episode, "Broken Bow". Other arcs covered the differences between the Klingons seen in Enterprise as compared to those seen in series set later in the Star Trek timeline. The season also featured a greater number of references to Star Trek: The Original Series with Orion slave girls and genetically engineered humans similar to Khan Noonien Singh appearing in a story arc which also featured the return of Brent Spiner to the Star Trek franchise.