Doctor Whois on the cusp of celebrating the franchises 60th anniversary later this year.

Tennants return to the franchise was a surprise, but Catherine Tates return as Donna Noble was equally surprising.

But who is Donna Noble?

David Tennant and Catherine Tate in Doctor Who

Image via BBC

Why did she and The Tenth Doctor ultimately have to part ways?

If accelerated, the morphogenesis of the young could be fatal to humans.

The Doctor and Donna shared many adventures.

Donna Noble (Catherine Tate) and Doctor Ten (David Tennant) in Donna’s first appearance in a Christmas episode of Doctor Who.

Image via BBC

Tennant and Tate had excellent chemistry onscreen, and they played off each other tremendously well.

Donna Noble served as the moral compass for The Tenth Doctor when he needed it most.

Conversely, The Doctor showed Donna the moral dilemma he constantly faces making impossible decisions.

doctor-who-unicorn-and-the-wasp-david-tennant-catherine-tate

Image via BBC

If there is a fixed point in time, nothing can be done to change it.

Donnas influence on the Doctor left reverberations for multiple lifetimes of the time-traveling Gallifreyan.

It was nice to see such a wonderful, platonic friendship depicted onscreen.

Catherine Tate as Donna Noble in Doctor Who 60th anniversary special

Image via BBC

The Tenth Doctor is not Donnas key in, since she likes macho, stronger men.

She was never attracted to The Doctor in that way.

Meanwhile, The Doctor was not looking for a romantic partner at the time.

The Sixth Doctor Colin Baker

Image via BBC

As The Tenth Doctor hilariously explained to Donna, “I just want a mate.”

He didnt want “to mate,” he wants a “mate” – a friend.

Donna more than fulfilled that role.

Doctor Who

Yet, their love for each other was unquestionable.

They forged a special bond that is rarely matchedbetween Doctor and Companion.

What Made The Doctor And Donna Noble Separate?

Catherine Tate

But that is not the end of Donna Nobles story in theDoctor Whosaga.

Donna appeared one last time in the two-part holiday special, “The End of Time.”

The process works on every human except for Donna and her grandfather Wilfred Mott (the lateBernard Cribbins).

Based on footage of theteaser trailer for the upcoming specials, The Doctor and Donna Noble will finally reunite.

Such a situation isnt necessarily unprecedented or impossible.

You might find yourself revisiting a few, but just the old favorites, eh?"

She says in the trailer, “Sometimes, I think theres something missing.

Like I had something lovely…and its gone.”

The ailment plaguing Donna of her memories burning her mind out is clearly still in play.

Despite Donna’s erased memory, it appears she still retains some muscle memory regarding old insults.

The Doctor’s restriction from traveling back through his own timeline is one of them.