Dennis Leary is an American actor, comedian, and writer, known for his sharp wit and observational humor. He gained fame in the 1990s with his stand-up comedy and has released several successful comedy albums. Leary is also recognized for his role in the television series Rescue Me, which he co-created and starred in, portraying a firefighter dealing with personal and professional challenges. In addition to his work in television, Leary has appeared in various films, including The Ref and Demolition Man. He is also an advocate for various causes, including fire safety and cancer research, and has been involved in charitable efforts through his organization, The Leary Firefighters Foundation.