Doctor Who: 8 Greatest Things Russell T Davies Contributed To The Whoniverse

For it's first year, the connection between Classic Doctor Who and the revival was relatively tenuous. Apart from enemies in common, and a Word of God confirmation that NuWho was in fact set in the same universe, there was very little to connect the two.

This changed in the series two episode School Reunion, in which Davies reintroduced Sarah-Jane Smith, a companion from the classic series, as well as the beloved robot dog, K-9.

For the first time, older fans could be certain that this was in fact the same Doctor Who that they had grown up with. The episode also allowed the chance to explore what happens to companions after the Doctor inevitably leaves them behind; a topic that was never really discussed in the classic series.

Sarah's return was so well received that it lead to a spin-off, The Sarah-Jane Adventures. The series ran for five series, the last of which was cut short by lead actress Elisabeth Sladen's tragic death from cancer.