[2] Set in the year 2020, the series follows the adventures of the Terrahawks, a taskforce responsible for protecting Earth from invasion by a group of extraterrestrial androids led by Zelda.

Terrahawks was less straight-laced than any of Anderson's previous series, featuring a wry, tongue-in-cheek humour as well as dramatic jeopardy.

The ensemble cast, with each member assigned a vehicle, had many similarities with Anderson's Thunderbirds, whilst the alien invasion plot was reminiscent of Captain Scarlet and the Mysterons and the live action UFO.

Prior to Terrahawks and throughout the entirety of the 1960s, Anderson's series were noted for their use of his Supermarionation technique, which made use of electronically augmented marionettes (the final series to use this technique was the live action/Supermarionation hybrid The Secret Service in 1969; Anderson switched to live action production beginning with 1970's UFO).

In contrast, producers of Terrahawks made use of latex Muppet-style hand puppets to animate the characters, in a process Anderson dubbed "Supermacromation".

[3] Tony Barwick, the series' most prolific scriptwriter, constantly used tongue-in-cheek aliases whenever he wrote a different episode, calling himself, for instance, "Anne Teakstein," and "Felix Catstein."

This was explained in a documentary on the special features disc of the series, in the Gerry Anderson book Supermarionation and the Terrahawks DVDs.

The final volume, "Zero Strikes Back", had a smaller print run than the rest of the tapes, and was quite a collectors' item, with copies generally going for around £100 on eBay until the series began to be released on DVD.

The opening title sequence begins with a video game playing on a screen when Doctor "Tiger" Ninestein appears and says: "Terrahawks!

Without the lavish budgets of his earlier television series, it was apparent to Gerry Anderson from a very early stage of production that it would not be possible to record full orchestral scores for Terrahawks.

In 2002, Fanderson records released a soundtrack compiling 75 minutes worth of music, the album included 3 of Harvey's Demo Themes for the show, 6 full episode scores and 3 surviving Kate Kestrel songs, "S.O.S", "It's So Easy" and the latter half of "Living in the 21st Century" which was used as the End Titles music in the U.S. syndication run.

Zelda and company are modelled after the oldest and wisest citizens of their planet, explaining their grey hair and wrinkled skin.

Characters who only appear in the Big Finish audio series include; A comic strip adaptation was drawn by Jim Baikie and Steve Kyte for Look-in magazine.

Showrunner is Mark Hoffmeier (Spider-Man, Nexo Knights, Marvel Super Heroes – Guardians of the Galaxy: The Thanos Threat) who is producing with Mike Penketh (Bob's Burgers, Gravity Falls, Wander Over Yonder and Tron) and Vicky Kjaer Jensen (Ninjago)".