Doctor Who: 14 Cool Details Revealed In David Tennant's The End Of Time Part One Commentary
9. Catherine Tate Expected Her Role To Be A LOT Smaller
While Donna's role in both parts of The End Of Time isn't huge, it's definitely more than a cameo. This isn't what Tate initially expected however, with the actress noting that she only thought she'd be returning for "one shot".
This is because of a conversation she had with Russell T Davies, not too long after Series 4 (and her departure in Journey's End) had been filmed.
Here, Davies told Tate that it would be "lovely" if Donna's wedding could be included in Tennant's final story, so the audience knows that Donna is okay.
Davies suggested that this might be just a single shot of the Doctor watching Donna get married, and because of this, Tate expected her role in The End Of Time to be really small - even as small as a single shot of Donna's wedding.