Split (2016) is a psychological horror-thriller directed by M. Night Shyamalan. The film stars James McAvoy in a groundbreaking performance as Kevin Wendell Crumb, a man with dissociative identity disorder who has 23 distinct personalities, each with its own unique traits and behaviors.

The story begins when Kevin kidnaps three teenage girls—Claire (Haley Lu Richardson), Marcia (Jessica Sula), and Casey (Anya Taylor-Joy)—and holds them captive in a secret underground lair. As they try to escape, they encounter various personalities of Kevin, including the domineering “Beast,” who emerges with violent intentions.

The film alternates between the girls’ attempts to outsmart Kevin and flashbacks that reveal Casey’s troubled past, offering insight into her character and survival instincts.

Split is notable for its exploration of trauma, identity, and the complexities of mental health. Shyamalan masterfully builds tension and suspense, culminating in a chilling climax that ties into his earlier film, Unbreakable (2000).

McAvoy’s performance received widespread acclaim, showcasing his ability to portray the nuances of multiple characters. The film blends psychological horror with thrilling twists, making it a captivating watch that challenges perceptions of identity and humanity.