From the early 1990s, Agou made documentary-style photographs in both black and white and color which take an allusive approach to the human condition. He also made short films and sculpture. In 1992, he moved to New York City. He began taking photographs in the streets that evoked a sense of longing and isolation. He made photographs at Ground Zero on September 11th, 2001, which were used in numerous publications. He first came to prominence with photographs taken in the New York City Subway, published in his book "Life Below" (2004).