Thunderbirds endures because it is "a family show for all ages", the star who voiced characters Parker and Brains has said.

It is 50 years to the day since the show, the brainchild of then husband and wife team Gerry and Sylvia Anderson, made its debut on ITV.

Filmed in Supermarionation, a puppetry technique involving fine wires and electronics, it depicted the adventures of the Tracy family who, as the secretive International Rescue, jetted around the world in amazing vehicles, performing daredevil rescues.

The very first episode aired was Trapped In The Sky, which revolved around nemesis villain The Hood's plot to photograph the Thunderbirds vehicles in action.

Despite a relatively short run between 1965 and 1968 comprising 32 television episodes and two feature-length films, Thunderbirds has now been part of British popular culture for half a century.

Speaking about the Thunderbirds Classic 50th Anniversary DVD, actor David Graham reflected on the show's remarkable endurance.

"Thunderbirds had a good story to tell," he said.

"The scripts contained adventure, suspense, superb visual effects and there was no gratuitous violence, but there was also an added leavening of humour. It's a family show for all ages."

At the age of 90, Graham is still tied to the series he first worked on when Beatlemania was at its height.

In April this year, a new CGI animation remake called Thunderbirds Are Go launched on ITV. The veteran actor has reprised the role of Parker, butler and chauffeur of International Rescue's London agent Lady Penelope.

The glamorous aristocrat is now voiced by Oscar nominee Rosamund Pike, who replaces co-creator Sylvia Anderson. Fonejacker star Kayvan Novak is the voice of Brains, also originally played by Graham.

Old and new come together on the DVD which celebrates the 50th anniversary with all 32 classic episodes and a documentary on the making of Thunderbirds Are Go presented by Reggie Yates. The second series of the new incarnation airs in 2016.

Over his long career, Graham has appeared in many television series ranging from The Avengers to The Bill. He has also voiced numerous characters in Doctor Who.

The Londoner is proud to be the only cast member from the 1960s still playing the same Thunderbirds role. Parker is a reformed criminal with a distinctive London accent and one of Graham's favourite memories is how the fan favourite was born.

"Gerry Anderson took me to lunch at a pub in Cookham, near to the studio in Slough. He wanted me to listen to an old waiter's voice so he beckoned him over and the waiter said, and I quote, 'Would you like to see the wine list, sir?'

"This was music to my actor's ear and the voice, which I elaborated on, became the voice of the much-beloved Parker."

As the show marks its 50th year, the future looks bright.

In addition to the Classic 50th Anniversary DVD and Thunderbirds Are Go, three new puppet-based episodes are being produced at the original studio in Slough thanks to a Kickstarter campaign.

Purchasers of the new DVD should look out for Graham's personal favourite episode: "A difficult one but, if you pin me down, I would have to say Vault Of Death because Parker was able to employ his legendary safe-cracking skills aided and abetted by his old mate Light Fingered Fred, who I also voiced."

Thunderbirds Classic Complete Collection Limited Edition DVD, ITV Studios Global Entertainment.