British Intelligence recruits him for an top-secret Middle East assignment ("Crisis in the Desert") to rescue an undercover operative.

Invisibility now is an avenue by which to help people who are besot with troubled predicaments, solve crimes and defeat enemy spies.

Michael Goodliffe, who plays the criminal scientist Crompton in the first story, is credited in the original release promotional documentation.

** In the unaired pilot episode The Invisible Man, the character's first name was Jane, but this was changed to Diane — or "Dee", as Brady himself usually refers to her — for the series.

The pilot, which bears the on-screen episode title "The Invisible Man" (but is often wrongly referred to as "Secret Experiment"), was never aired.

Despite that this Invisible Man was never transmitted, plot elements and footage from it were reused in the episodes "Secret Experiment", "Picnic with Death" and "Bank Raid".

Subsequently, in "Picnic with Death", a motoring accident fully exposes Brady's invisibility, to the point that he is besieged by the Press.

Tim Turner provided Brady's voice, also without on-screen credit, using a transatlantic accent in order to help ITC sell the series to the United States.

The various 'actors' playing Brady's body remain unknown to this day, apart from Tim Turner whose identity was revealed in 1965 (the series was still being repeated regularly up until 1966).

"[3] Tim Turner himself appeared visibly in the "Man in Disguise" episode, though on this occasion he played Nick, a foreign-accented villain who impersonates Brady.

Among the writers recruited for the show were Ian Stuart Black, Michael Pertwee and Brian Clemens under the pseudonym Tony O'Grady.

Puppeteer Jack Whitehead, who had earlier worked on Muffin the Mule, was called in to provide the brilliant special effects of the show – such as cigarettes smoking while hanging in the air and wine being drunk by an invisible drinker (The pilot episode credits "Trick Photography" by Victor Margutti).

Stuntmen risked their lives hiding in the bottom of cars, driving the vehicle while looking from a slightly open door, or in the steering of a motorbike from a sidecar, which caused members of the public to try and stop what they thought was a runaway vehicle; they didn't realise there was actually a stuntman concealed in the sidecar, steering the motorbike with duplicate controls.

[4] In the second series, the camera often took on Brady's point of view, i.e. showing whoever and/or whatever the character himself was seeing at the time, which meant that the need for special effects could be cut down.

Unfortunately, when the series was commissioned and went into production, Patterson was found to be committed workwise and so his place was taken by another Canadian actor, Paul Carpenter, a former band singer and B-feature leading man.

Casting director Harry Fine and sound supervisor Fred Turtle also worked on both series Guest stars included Peter Sallis, Leslie Phillips, Irene Handl, Honor Blackman, Patrick Troughton, Dennis Price, Dermot Walsh, Willoughby Goddard and Ian Hendry.

Stars Lisa Daniely, Deborah Watling, Lloyd Lamble, Bruce Seton, Ernest Clark, Michael Goodliffe, voice of Peter Brady: Lee Patterson.

With the help of local resistance fighter Yolanda, Brady plans to rescue the agent from a high-security hospital before he reveals this knowledge to Omar.

Network released the entire series in the UK as a four-disc DVD set using new prints made from the original negatives.