I mean if you haven't seen it yet, Wizard of Lies on HBO is a Soprano's-level of quality depiction of the whole Madoff thing.
He spent the better part of a decade trying to alert the SEC to what he found. It was certainly a risky endeavour given how much money was at stake.
[0] https://duckduckgo.com/?q=harry+markopolos+no+one+would+list...