The Brady Bunch S01E22 - The Possible Dream

When Cindy accidentally puts Marcia's diary in the collection of books to be donated to a local book drive, Marcia is crushed when she finds out what happens and vows to never speak to Cindy again. The family then sets out to find her diary before a stranger can read her deepest, darkest secret is that her crush is Desi Arnaz, Jr.