Some spinoffs seem obvious (The Paternoster Gang, Counter-Measures), others are demanded by fans (Jago & Litefoot), and some just seem unexpected. This set falls into the final category. I don't know if anyone was clamouring for a Donna Noble spin-off series, and if they were it seems odd to set it after Forest of the Dead rather than between The Runaway Bride and Partners in Crime.

Having said all that, I actually rather enjoyed this story. The prickly relationship between Donna and her mum Sylvia is here, and we get a bit more insight into what the young Donna got up to during her schooldays when she meets up with her old friend Natalie. We also get to listen to Donna making up nonsense backstories for herself when forced by Sylvia into attending a speed-dating session. Of course, in the world of Doctor Who, nothing is ever as simple as that, and soon Donna and Natalie are hot on the trail of a series of mysterious disappearances, and tangle with vivisectionists, aliens, and a speed-dating organiser who won't take no for an answer.

For me, this shows that, when written well, Donna Noble is one of the stronger companions in the history of the show, and well worth her own series.