When most people think of a hero, they picture Superman swooping through the air to save the day in its most dire moments. But these 21 real-life heroes have saved the world in much more realistic, admittedly less grandiose, ways.

 

21. Frank Serpico

This New Yorker is known for whistleblowing on police corruption in the late 1960s and early 1970s. His actions prompted Mayor John V. Lindsay to appoint the landmark Knapp Commission, which investigates corruption within the NYPD. As a result of Serpico's efforts, the NYPD was drastically changed. Michael Armstrong, who was counsel to the Knapp Commission and went on to become chairman of the city's Commission to Combat Police Corruption, observed in 2012 “the attitude throughout the department seems fundamentally hostile to the kind of systemized graft that had been a way of life almost 40 years ago.”

Much of Serpico's fame came after the release of the 1973 film Serpico, which was based on the book by Peter Maas and which starred Al Pacino in the title role, for which Pacino received an Oscar nomination.