On October 29, 1966, millions watched as the familiar face of the Doctor changed for the very first time… During the closing moments of The Tenth Planet, episode 4, viewers were introduced to the Second Doctor, played by the brilliant Patrick Troughton.

The following week his adventures began with a trip to the planet Vulcan (recently referenced in Asylum of the Daleks) where he faced his oldest adversaries. He bowed out in the 1969 epic The War Games but returned on a number of occasions to battle mad Time Lords, a Yeti and even the Sontarans!

To celebrate the anniversary of the Second Doctor’s first appearance, we’ve created a new gallery that looks back on his adventures and companions.

You can watch clips and find out more about his travels by checking out his first season (including two Dalek adventures), his second season (packed with terrifying monsters!) and his dramatic third season, which included UNIT’s explosive debut.

Happy anniversary to the Second Doctor!