Sidekick-o-rama : Ianto Jones

When Ianto first appeared in Torchwood, he seemed a bit of a nothing character. The general dogsbody/butler type.


And then early in the first season, it was revealed that he was keeping his cyberman-ized girlfriend in the basement without the team's consent.
Yeah, that first season was bad and did suggest that Captain Jack didn't run the most thorough of personality tests on his new recruits what with others sneaking aliens in or turning out to be psychos.


In time though Ianto and Jack become lovers. It's done in as subtle a way as first season Torchwood gets in that we just mostly get hints and snarky remarks from the other characters. 


Ianto is a more confident character in season two. And a wittier and more action-y one too. Maybe it's because of the strength of  his romance and because he was no longer keeping secrets. Maybe it's because the writing staff had finally figured out what to do with him.
He's now out of the underground lair and kicking ass whilst being hilarious. (If you ditched Torchwood after the first season, go watch the second one and buy Children Of Earth - you'll thank me for it).
All that said, there is a melancholic edge to his relationship with immortal age-less Jack as shown in the radio play The Dead line by Phil Ford:
"But let's be honest, Jack. I'm… nothing more than a blip in time for you, Jack. Every day, I grow a little older. But you're immortal."
The third series, Children Of Earth, introduces us to Ianto's sister and her family and how he still has to lie to them about both his job and his private life. It's very well-played and echoes the lies he used to tell
And by the tragic conclusion of the season, his character has grown from the dusty bureaucrat to a likeable hero. 

Sidekick-o-rama : Frobisher

Colin Baker's sixth Doctor perhaps wasn't best served by his TV stories.

He was written too moody, even trying to murder his companion in his debut story as well as pushing a foe into an acid bath early in his run.

Character aside, the plots were mired in continuity. Witness Attack of the Cybermen which required knowledge of an 18 year-old TV story that at that time the BBC had lost.

But his strongest stories were in the Marvel comics.

As had been the norm with previous regenerations, the Sixth initially had a comics-only companion.

Writer Steve Parkhouse decided to take full advantage of the unlimited special effects budget and go with a shape-changing alien who chose to stay as a penguin for "personal reasons".

Doctor Who : Voyager. (Parkhouse, Ridgway, Hart)

Frobisher was a Philip Marlow-esque private eye. We first meet him disguised as a telephone, investigating an adulterous husband.
It's quite apt that the Doctor in his supposedly shape-changing Tardis is accompanied by a shape-changer who stays in just as incongruous a form.

Doctor Who : Voyager. (Parkhouse, Ridgway, Hart)

He's a charming addition to the Who myths and a rare example of a TV franchise taking advantage of the artistic freedom of comics.
Also, somewhat improbably, some of his tales were written by future comics great Grant Morrison, including Frobisher's last as a regular companion to the Sixth Doctor.
They're available in reprints and are well worth a read.

Sidekick-o-rama : Harry Sullivan (companion to the 4th Doctor)

Harry Sullivan (Ian Marter)

Poor Harry seems to have faded into obscurity.

He accompanied Sarah Jane Smith and Tom Baker's Doctor for a season and, well, it's easy to be eclipsed by those two.
In many ways, he was the prototype of current companion Rory.

It's hard for writers to create memorable male companions who don't detract from the Doctor. (I can only think of moody Turlough and, arguably, Captain Jack).
Harry's purpose was to be the man of action as the producers had wanted to go for an older Doctor. This was made rather pointless when they cast Tom Baker.
So Harry evolved to be sweet albeit a bit hopeless. Witness this lovely scene from Revenge of The Cybermen.
Harry was a Navy medic and acted as a nice counterpoint as the show switched from an establishment-friendly Third Doctor often working with the military to the iconoclastic Fourth.
His old-fashioned decency stands out. Yeah, he's a figure of fun sometimes but he does the right thing.
And his unrequited unspoken love for Sarah Jane is rather sweet looking back.

He's a bit of a third wheel and who hasn't been there?
And his run managed to include all-time classic Genesis Of The Daleks.
Also, a few years later Ian Marter, the actor who played him, wrote a spin-off novel in which Harry found himself embroiled in Van Gogh-related espionage.

My old French exercise book suggests that I regarded this as the best book I'd ever read. To be honest, this might not still be the case.
But few other companions would come close to inspiring something like this.