Justin Bartha is an American actor and producer, best known for his role as Doug Billings in the popular film series The Hangover. He was born on July 21, 1978, in Fort Lauderdale, Florida, and grew up in a Jewish family. Bartha began his career in theater before transitioning to film and television. In addition to The Hangover, Bartha has appeared in various films and TV shows, including National Treasure and the series The Good Fight. He has also worked as a producer on several projects, showcasing his versatility in the entertainment industry.