[s4e1] Partners In Crime -

But the reunion was cut short. Miss Foster wasn't just selling pills; she was using London's population as a surrogate nursery. With a flick of a remote, the "miracle" began. Across the city, thousands of tiny, marshmallow-like creatures—the Adipose—began to spontaneously generate from people's stored body fat. They were cute, sure, but the process was lethal if fully completed.

The Doctor grinned, snapping his fingers to open the doors. After a missed chance and a long search, the girl in the wedding dress had finally become the partner in time. [S4E1] Partners in Crime

They were both investigating , a company promising a miracle weight-loss pill that claimed the fat just "walks away." While the Doctor was busy lurking in shadows and waving his sonic screwdriver at suspiciously high-tech necklaces, Donna was doing some undercover work of her own—armed with nothing but a notepad, a powerhouse personality, and a very large hat. But the reunion was cut short

No words were needed. The sheer absurdity of the moment—the frantic miming, the "What are you doing here?!" mouthed through the glass—was enough to bridge the years since they’d last met on a runaway wedding bus. After a missed chance and a long search,

The London sky was thick with the kind of industrial fog that usually signaled either a looming cold or a looming alien invasion. For the Doctor, it was just a Tuesday. But for Donna Noble, it was the day she was finally going to find him again.

We could explore to a different planet or see how her grandfather, Wilf , reacts to her sudden disappearance into the stars.

Working as a team again, the Doctor and Donna managed to shut down the induction loop, saving the people of London even as the little Adipose toddlers began their trek to the roof to be collected by their nursery ship.