Robert Langford Modini Stack was a multilingual American actor and television host. In addition to acting in more than 40 films, he also appeared on the television series The Untouchables and later served as the host of Unsolved Mysteries. Born in Los Angeles, California, Stack spent his early childhood growing up in Europe.  Becoming fluent in French and Italian at an early age, and he did not learn English until returning to Los Angeles.  Stack achieved minor fame in sporting, winning multiple championships including setting two world recor…