Dennis the Menace and Gnasher

The Secret Diary (1x11)

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Hiding from the wrath of Dad after a chaotic morning (aided by Granny), Dennis comes across what he thinks is his Dad's diary, and realises that in his youth he was far from the respectable young man he claimed to be. Soon, the diary entries make Dad a reluctant celebrity, and with a Hollywood film director making a film based on the book, Dennis discovers that his antics are no longer seen as threatening.