5. School Reunion
As mentioned in the previous entry, the return of a previous companion is exciting anyway. But if that returning companion is one of the most famous and enduring in the show, that makes it more special. When it was announced Sarah Jane Smith, played by the late Elisabeth Sladen, was returning for the show (which proved to be a springboard to a spin-off), fans of the classic series were suitably excited. And when Ks also made an appearance, it made this episode even more special. The Doctor, Rose and Mickey run into Sarah Jane and K9 investigating a school, which proves to be the hideout for a viscous race of aliens called the Krillitane. The episode is good not just plot wise, but in how the characters, especially Rose, react to one another. The Doctor is understandably excited and pleased to see such a fond and remembered companion, and Mickey takes a shine to Sarah due to the exact same surname. But Rose reacts differently - she sees what she has to do to be remembered by the Doctor, to become his 'favourite'. Bravery, strength, and courage are or have been all shown by Sarah Jane - and from this moment on, Rose strives to be this. The episode marks a turning point for her, and for this reason the episode is fondly remembered.