Martha Mitchell Wa the wife of John Mitchell. John was a partner in a law firm with Nixon and Nixon later appointed him to be the US Attorney General. Martha and John lived in the Watergate apartment complex. She was a popular socialite and appeared regularly on TV shows. She riffled through her husband’s paperwork and found evidence of the wiretapping/break in (among other things) and leaked in the info. She also ended up being kidnapped!

Anyway, her role in the scandal being discovered is larger than history credits.

https://en.m.wikipedia.org/wiki/Martha_Mitchell