We’ve just come from an exclusive screening of the first two episodes of the new series of Doctor Who at the giant concrete Tardis that is BBC Television Centre.

We reckon hardcore Who fans will be split down the middle about the return of Catherine Tate as onetime runaway bride Donna Noble, who this series becomes the Doctor’s full-time intergalactic companion.

The slightly silly series opener sees the pair reunited while investigating a diet pill company run by the sinister Miss Foster, played by former Coronation Street actress Sarah Lancashire. It turns out that Foster is an evil alien (natch!), which means it’s up to the intrepid Time Lord and his new assistant to stop a million overweight Brits being turned into sickeningly cute alien babies.

The second episode, set in ancient Pompeii on the eve of Mt Vesuvius’ huge eruption, features guest appearances from Phil Davis and Peter Capaldi. The real stars of the show, though, are the evil Pyrovillians, a clan of terrifying fire monsters who live deep inside the volcano.

The episode also gives Tate the chance to show more fire (sorry!) alongside the always charming David Tennant. She even manages to nab some of the show’s funnier lines from under his nose. Talking to a teenage Pompeiian, Donna asks: ‘What do young people do around here? Hang out at TK Maximus?’

It remains to be seen if viewers will warm to Donna as much as they did Martha and Rose, but early indications look promising.