Doctor Who: 13 Cool Details In David Tennant & John Barrowman's Last Of The Time Lords Commentary
4. John Simm Was Worried About His Final Line
The Master suffers yet another death at the end of Last Of The Time Lords, with the character being gunned down by his abused wife, Lucy Saxon.
It's hard to disagree that she was right to shoot him, but in a weird way, she was actually doing him a favour. As the Master's final line hints ("Will it stop Doctor... the drumming... will it stop?"), he's desperate for the drumming inside his head to end, and in death, he might finally be granted that peace.
His whole arc in this story works very well, but speaking of that final line, not everyone was convinced it was the right one to go with. Specifically, John Simm was "really worried" about the Master's final words, according to Tennant.
Tennant doesn't elaborate on what Simm was worried about, but it was possibly just a general sense of concern surrounding the scene, a general anxiety that such a pivotal moment wouldn't be as good as it could possibly be.