Peter Thiel's venture capital fund, Mithril Capital Management, has accused its ex-general counsel, Crystal McKellar, a former child actress known for her role on the "The Wonder Years," of launching a "whisper campaign" to discredit the firm and lure away its investors. 

"Swampy" is how McKellar described Mithril, which Thiel, a billionaire investor and entrepreneur, co-founded with Ajay Royan. She added in an email that the "allegations of wrongdoing are unequivocally false, and it will be a simple matter to prove them false if it gets that far."

Mithril filed a complaint against McKellar on Wednesday in Travis County District Court in Austin, Texas, where the firm is headquartered.