We had a 'phantom shitter' on our ship when I was in the Navy. The classic was one in the middle of the officer's ward room dining table right before some Viet Namese officers came aboard for lunch. The guy was good because nobody saw him do it. The officer's Filipino ward room waiters went crazy trying to get things cleaned up before the skipper came in with his guests.
We had an idea who it was but he was never caught and it stopped when he was transferred.
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"I didn't care what she didn't 'low--I would boogie-woogie anyhow" John Lee Hooker