"Of course you weren't going to do anything," Sherlock replied acidly; he wasn't waiting for her--in fact, it distinctly appeared that he was trying to leave her behind. "If I'd thought you were going to do something, I would have defended myself instead of just getting up. Fortunately for you, I found no reason to do so."

Sherlock had already familiarised himself with the layout of the island; finding his way to the door of Day's office was not exactly a challenge.

He knocked, twice; then, without waiting for a response, took the doorknob and let himself in. He walked right up to her desk, stopping about a yard away. "I would strongly advise against trying to poison me," he declared, facing her calmly, as though he feared nothing of her--or just didn't care.