Doctor Who: Every Doctor's Definitive Seasons

The Second Doctor: Season 6

It's a particularly difficult task to pick just one season from the Second Doctor's tenure, considering each of them hold stand out classic gems. But then you remember that Season 6 holds both The Invasion and The War Games.

These tales have been cemented in the fandom's minds, ultimately becoming the highlights of the Second Doctor's era. Although one can't forget about other enjoyable serials, such as The Mind Robber, and The Seeds of Death. Furthermore, this saw the Second Doctor's best TARDIS team come into full fruition, after Zoe was introduced in The Wheel in Space at the end of the previous season.

Jamie had been a loyal companion since the Second Doctor's second outing, The Highlanders, and had become like a best friend, and it shows perfectly through the writing, and Patrick Troughton and Frazer Hine's onscreen chemistry. The addition of Zoe rounded everything off, through her impeccable genius when it came to computers, and not to mention her strong confidence, and bravery in the face of danger.

Another noteworthy element to Season 6 was the introduction of UNIT. Though Alistair Gordon Lethbridge-Stewart made his debut in Season 5 (The Web of Fear), The Invasion was his first appearance in the rank of Brigadier. This serial is simply a joy to watch, spanning over eight thrilling episodes, depicting one of the most callous, power hungry human villains in the show's history - Tobias Vaughn, on top of an iconic Earth invasion story, which would go on to shape the foundations of the Third Doctor's era.

Also, The War Games saw the first appearance of not only The Doctor's home world, Gallifrey, but also a full introduction to his people the Time Lords.