Draco had been having such a good day. He was planning a piece on the best lunch in London, which meant he was getting to visit all his favourite places to test out their current lunch menus. Today had featured a really very nice lobster in a cucumber-melon sauce that Draco had been extremely dubious of but which had turned out to be surprisingly pleasant. After that, he'd spent an hour in his study re-ordering the lunches he'd already had in order of preference. It was the best kind of work - no deadline, and Draco enjoyed the thought of putting together a list that people would refer to for weeks rather than just a few days.
It was only when he left his study and descended to his potions lab that Draco's day started to turn on him. The flobberworm mucus he'd ordered from his apothecary of choice, which had duly been delivered and taken in by the house-elves, was not flobberworm mucus. It didn't even look remotely like flobberworm mucus, though as it had been wrapped when it arrived Draco could hardly blame the house-elves for that. The apothecary would be closed, by now, and if Draco didn't add the mucus tonight his currently-brewing batch of Dreamless Sleep would be ruined. He had enough for this evening, and for a few more days after that, but not enough to see him through until he could brew more.
Intending to give his apothecary a piece of his mind as early as possible the next morning, Draco appatated to Adrian's building. Adrian would have supplies, and Adrian would be willing to lend them. The downstairs shopfront was dark and empty, so Draco carried on up to the lab above, knocking hard on the door.