Then the science began.

“Right,” she muttered. “You win.”

Not slowly. Not grudgingly.

The water sat in the sink like a dark, oily mirror. It hadn’t moved for three hours. Jenny poked at it with a spoon, and a foul belch of old food and grease bubbled up.

She scooped out a generous cup of the bicarb—clouds of fine dust puffing up—and tipped it straight into the murky drain hole. It sat there like dry snow on a black pond. Then she poured the vinegar. Not all at once, but in a steady, glugging stream.

She’d tried boiling water. She’d tried the rubber plunger until her arms ached. The only thing left was the small orange box under the sink, pushed behind the bleach: bicarbonate of soda .

The foam bubbled over the rim and slid lazily down the sink’s side. Jenny let it work for a full ten minutes, then poured the kettle—boiling hot—straight into the chaos.