Katy Manning As Jo Grant
Personally my favourite Doctor Who companion of all time.
I love the relationship between Third Doctor (Jon Pertwee) and Jo Grant (Katy Manning), they seemed close in real life too.
She is lovely and did some of the best stories ever, i think the 1970s stories with Third Doctor, Jo Grant, Delgado as The Master and The Brigadier/Unit, not much can beat them.
I was sad that Caroline John left after 4 stories, i liked her very much but i love Jo Grant.
Terror Of The Autons, Mind Of Evil, The Daemons, The Curse Of Peladon, The Sea Devils, The Three Doctors all are great.
I much prefer her to Sarah Jane and while i prefer Hartnell and Tom Baker as The Doctor, i do think Jon Pertwee and Katy Manning had the best Doctor/Companion relationship.
And by the way, Happy 70th Birthday to Katy Manning.