Doctor Who: 10 Best Companion Performances In NuWho

Although Donna had firmly established her place in the heart(s) of the fandom by this point, subsequently becoming one of the all time favourite new series companions, the Series 4 finale The Stolen Earth/Journey's End is probably the place that Catherine Tate gets to display the widest range.

For starters, she has an awful lot to do. She has to offer the regular Donna sass whilst combining it with Donna's lack of real self-confidence... and do it naturally. All while having to stand out among a smorgasbord of character cameos and returns.

But that's not all. As the episode reaches its dramatic climax, she has to become the DoctorDonna, too. This means that she needs to act in a manner that will be convincing for a half Time Lord. Suddenly she has to increase the speed her character is talking at and make her appear to be casually thinking on a cosmic level. 

Then, she has to play through the heartbreaking emotion of Donna's exit, portraying the fear the character feels at losing her memories of the Doctor. And then Tate has to forget all the development the character has seen and play Donna as she was at the start.  She pulls it off, of course, and it makes for an incredible performance along the way.