Born in 1964, he is an American screenwriter, director, and producer known for his work in television and film. He gained prominence as the creator of the cult TV series "Buffy the Vampire Slayer" and its spin-off "Angel." He also created "Firefly" and "Dollhouse." In film, he directed "The Avengers" and its sequel, "Avengers: Age of Ultron," contributing significantly to the Marvel Cinematic Universe. His work is noted for strong character development, witty dialogue, and ensemble casts.