<Li> Chloë Grace Moretz as Susannah Cahalan, a young woman who one day wakes up in restraints in a hospital a month after suffering from a mysterious illness that doctors are unable to diagnosis </Li> <Li> Jenny Slate as Margo, a friend and co-worker </Li> <Li> Thomas Mann as Stephen, Cahalan's boyfriend </Li> <Li> Tyler Perry as Richard, Cahalan's boss at the New York Post </Li>

Who is the boyfriend in brain on fire