Barney (Greg Morris) uses a tracking device to follow the shipment of drugs after he plants fake drugs with homing devices concealed inside. An identical tracking device (a ballpoint pen mounted on a pivot above an "on" and "off" switch) will reappear in the episode Blast (1971) later this season.
This is one of the few episodes where Jim doesn't receive instructions on what to do with the tape at the end of the message ("This tape will self destruct in 5 seconds."). However, there is a burning barrel next to Jim, and he just throws the tape in.
Lesley Anne Warren sings in this episode.
A scene in which Phelps (Peter Graves) recruits Dana (Lesley Ann Warren) into the IMF was filmed but left out, because of uncertainty as to when this episode would be aired. In the event it was the second telecast of the season.
Obvious stunt double for Barney when the script called for him to climb down the back of the moving truck after planting the homing device, and then leap off down an embankment.