S15E04 The Regina Monologues
The Simpsons visit London,where Grampa hopes to meet his old sweetheart Edwina. Confused by the London traffic system Homer accidentally rams Queen Elizabeth's coach and gets put in the Tower of London. Escaping through a secret tunnel he ends up in the queen's bedroom but she agrees to let him go back to America as long as he takes Madonna with him. At the airport Grampa finally meets Edwina and her daughter - who looks and sounds a lot like Homer.