The script called for Samantha to hum in the elevator but didn't specify what to hum. She initially planned to hum the MacGyver (1985) theme as a prank on Richard Dean Anderson but couldn't remember it, so improvised by humming the Stargate SG-1 (1997) theme.
The character of Pete Shanahan is played by David DeLuise, one of the younger brothers of producer Peter DeLuise. All three DeLuise brothers, Peter, David and Michael DeLuise, and their father, Dom DeLuise, have all appeared in episodes throughout the series.
The role of Pete Shanahan was written for Ben Browder (Lt Col Cameron Mitchell from season 9 onward) but he was unavailable.
In the opening scenes, Sam Carter states that there is no zoo in Colorado Springs. In fact there is a nationally renowned zoo, the Cheyenne Mountain Zoo, in Colorado Springs which was founded by Spencer Penrose and incorporated in 1938 by Penrose as a non-profit public trust for the citizens of Colorado Springs.
The building exterior featured in the opening shot is the University of Chicago Laboratory Schools in Hyde Park, Chicago, IL.