[AaronTV]

I do think the Mirror have been quite unfair here - it was probably always Russell’s plan to have a new companion for season two, with Millie doing a handful of episodes. I also personally think it’s looking quite likely Ncuti will only do two full seasons, so I’m guessing Russell wanted a different dynamic before Ncuti potentially leaves.

Companions staying for long stretches has become much more common in recent years, but going back to 2005 they tended to be much shorter stints.

Freema Agyeman, for example, only did a single series as Martha and from what I can remember Russell had always planned another companion for the fourth series, which eventually became Donna’s return. Martha was always intended as a returning character, however, including in the show’s spin offs, so I wouldn’t be surprised if Millie turned up in the future too.

IIRC the tabloids also spoiled Catherine Tate returning for Series 4 before Freema’s episodes had even aired, which in turn confirmed Freema was leaving.