You can't find him!
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You open the door to his room. Empty and clean and smelling of polish. But what's this on the dresser?
Locked with Cat: Getting Warmer 50
No Disgruntled Naval Officer and no Screaming Map
It's just a scrawl on a napkin, but perhaps it marks a little of the way to Polythreme. You still need to find him if you ever hope to go there, though.