Mrs. Queen Takes the Train by William Kuhn
" 'Is this all there is?' The Queen thought to herself. She'd begun her adventure in such high spirits and now she sat next to a sign directing visitors to the gift shop on her decommissioned yacht where once had stood an ebonized side table."
What would happen if the Queen of England, in a whimsical mood, left the castle without fan fare and wandered about London by herself...in a hoodie jacket? Whimsy indeed!