Two holes have I

But I do not see

You'll find the next clue

Inside of me.

Sherlock had awakened to find John gone. The note was taped to the bathroom mirror. His eyes narrowed as he took it down. The skull, of course.

He lifted it from the mantel, to find another note:

I help you to think

(Don't spill coffee on me)

I sit atop laps

Come find clue number three.

"Interesting," Sherlock said, opening the laptop.

On the table you'll find

Directions to John

And then you'll find out

What's going on.

On the kitchen table:

Sorry, wrong! Got you!

Now isn't this fun?

Try again, Sherlock.

Go back to one.

He scowled, glancing around the flat. Two holes? Looking, thinking, minutes. "Got it," he said, grabbing tweezers from the microscope table.

Inside his violin:

Now you're on the right track

Bully for you!

Time to revisit

Clue number two.

More minutes. Coffee? Thinking? Laps?

The stained throw blanket on the couch, unfolded, a note pinned inside:

The table, now, Sherlock.

That only you use

Look for the six

The last of the clues.

"Don't even need to look," Sherlock smiled, trotting down the stairs to the basement flat. Atomic number six. C. 221C.

He opened the door. Dark, silence. Then lights, people, presents, food, shouting: "Happy Birthday!"