Although 'Skydiver Operative' (played by Georgina Moon) was never given a name in the series, the scripts identify her as Lt. Sylvia Howell.
First appearance, in broadcast order, of a new SHADO VTOL (Vertical Take Off Landing) aircraft.
The original script had Captain Peter Carlin (Peter Gordeno) being taken by the aliens instead of Foster, solely to highlight Gordeno's dancing talents in the party scenes.
Deleted scene: Alec Freeman arriving at the party and conversing with Foster and Sylvia Graham.
Paul Foster sings Beautiful Dreamer at the end, composed by Stephen Foster.