The darkness was almost palpable; a rank, fetid darkness that crept through the sewers and into every crevice of the cloak Lucius wrapped tightly around himself. "Lumos" he intoned for the fifth time, but something in the Stygian gloom stifled even magically-conjured light. The blond-haired wizard muttered an imprecation against the pedigree of his Dark Master, and pressed on through the sludge, trying hard not to think of what the sludge was doing to his boots at the same time. His hands brushed the walls on either side, attempting to keep balance and find a way out.
Ten minutes more, and several hundred miasma-laden meters further on, his gloved hand discovered that there was a passage to the right. Unfortunately, this was at the exact moment that his right foot discovered a loose and wobbly brick in the floor. Lucius fell heavily into the stench, the slime sloshing over his clothes in a noisome "splash".
"Devil take them, and their stupid hideaway." He pulled himself to his feet, considered the mess, and decided to deal with it after locating the supposed Death Eater lair he had been seeking. He made a slow and painful (not to mention smelly) essay into the side tunnel, feeling each step before putting his weight on the bricks. The tunnel end was only three yards away, however, and Lucius allowed the despair of extreme frustration to overtake him as he slumped against the facing.
"I don't suppose they've even been down here" he muttered to himself, adjusting the right glove which had slipped up and allowed a little muck onto his palm. A slight unsteadyness revealed another problem, and Lucius stood on his left foot and rested his right hand against the tunnel end while he investigated what had caused it. "And that's the heel of my good boot - mudbloo.....!"
To say that Lucius was surprised when the brick under his hand levered downwards with an audible "click" would be an understatement. To say he was displeased when he once more measured his not-inconsiderable length on the tunnel floor would also be a disparagement of his feelings. But to describe the feelings of the gentleman within the chamber in any way, when faced with the sudden intrusion of a tall, slender, shit-covered wizard, would be to completely belittle their importance.
It was possibly the fumes rising from the puddle beside his face, but Lucius was having hallucinations. After all, an elegant dinner table set for two was not that unusual an item, and the exceedingly handsome man in full Muggle World War Two RAF battledress might be waved away as the product of tiredness and mild poisoning. But the man's dinner companion, elegantly attired in a fine Crepe de Chine pleated dress and sporting a diamond necklace was, without doubt, a sheep.
Lucius did what anyone else could gladly forgive him for - he fainted.