[Puzzle 004]

[A dejected little boy young gentleman in blue sits in the library today at a table, journal open off to the side. In front of him is a book with a red cover, full of intermediate-level puzzles and riddles. There's a piece of paper beside it, on which he solves most of them - if they require paper.

There are a few interesting ones copied down into the journal, for reference later.

YYHLYEYT?
6L=12 6S=18 6LS=?
Meanwhile...

After a while, Luke sighs in a most ungentlemanly way.]

I wish I knew why this book feels so important. [the sound of ruffling pages] Maybe if Professor Layton were here he-

[Luke cuts himself off almost sharply, closing the puzzle book and doodling a few little pictures of fish and mice instead. One of the little mice wears a tall top hat.]

I wish I could go home.