This is big, silly, popcorn-Who. If you don't like manic, improbable, Earth shattering events followed by swift, improbable solutions then you might find it difficult to get on board with this. It is at this point, after having a big returning villain each year across new who, that they started to get into the B-list menaces (Macra notwithstanding). At the time of transmission, for the the average viewer over 30, Sontarans were one of those "you might remember these guys" threats. They are served adequately, fulfilling their own little niche in the show - the war mongers with a taste for honourable death.

There are pandering inclusions including mentions of the Rutans and the first of many ham-fisted nods to the Brigadier that the 21st century run offers up. At this point in time, it would have been a much more satisfying route just include Nicholas Courtney in the show. A missed opportunity now. But then you have Martha's return(!), Donna fighting aliens solo(!), Wilf being a sweetie(!), the fully fledged return of UNIT(!) All engaging sugary treats.

In retrospect, the most ahead of its time aspect that this two-parter serves up is a secondary human villain who is built in the mould of Mark Zuckerberg or Elon Musk. He is a t-shirt wearing, tech company owner who wields serious power which he puts to dubious use - something the show could do with revisiting.