10 Saddest Doctor Who Companion Exits

The ending of The Green Death and Doctor Who's tenth season, is a celebratory one. There's a party and, in a much-needed portrait of unity, stuffy military types rub shoulders with progressive environmental activists. So why is Jo Grant's departure the saddest companion exit?

Throughout the story, the Doctor is coming to terms with the fact that his companion has outgrown him. She turns down the chance to visit Metebelis 3 to join the protests in Wales, where she spends an increasing amount of time with Cliff. The Doctor can see that she's falling for a younger, more handsome, more human version of him, but is unable to voice his sadness.

With the party in full swing, and Jo leaving her life in the TARDIS behind, there's a melancholy note to proceedings. Without saying goodbye, the Third Doctor quietly departs from the festivities, gets in his car and drives away into the twilight. It's such a memorable moment that Steven Moffat and Mark Gatiss later referenced it in the Sherlock episode The Sign Of Three, when Holmes departs John and Mary Watson's wedding in a similar fashion.