Time Served: Four months in 1997, one year in 1999
Robert Downey Jr. hasn't always acted like a superhero. The A-lister spent time behind bars in 1997 and 1999 for several drug-related run-ins with the law. In June 1996, police found crack, cocaine, heroin, and a pistol in Robert's car after he was pulled over for speeding near his Malibu, Calif., home. The actor was charged with a DWI, possession of a concealed weapon, and possession of controlled substances. That same year, Robert passed out in a neighbor's home after breaking in while under the influence. He was put on probation for his crimes -- but landed in jail for four months in 1997 after missing a drug test. He spent almost a year behind bars in 1999 when he missed yet another drug test.