"Long Day's Journey into Night" is a semi-autobiographical play by Eugene O'Neill, first published in 1956. The story unfolds over a single day in the life of the Tyrone family, revealing their struggles with addiction, illness, and emotional turmoil. The characters include James Tyrone, a financially successful actor, his morphine-addicted wife Mary, and their two sons, Jamie and Edmund, who face their own personal demons. The play explores themes of family dysfunction, the impact of the past, and the search for redemption. It is known for its raw emotional depth and realistic dialogue, reflecting O'Neill's own family experiences. The work is considered a classic of American theater and has received numerous accolades, including the Pulitzer Prize for Drama.