Jacob's Ladder is a 1990 psychological thriller / horror film directed by Adrian Lyne, based on a screenplay by Bruce Joel Rubin. It stars Tim Robbins, Elizabeth Peña, Danny Aiello, and Jason Alexander. Actor Macaulay Culkin appears briefly in an uncredited performance.
Jacob Singer (Tim Robbins) is a U.S. soldier in the Mekong Delta during the Vietnam War. When the story begins, helicopters are passing overhead, carrying supplies for what seems to be preparations for a big Viet Cong offensive. Without any warning, Jacob's unit comes under fire. The soldiers try to take cover but begin to exhibit strange behavior for no apparent reason. Jacob attempts to escape the unexplained insanity, only to be bayonetted by an unseen enemy.
The film then shifts back and forth from Vietnam to Jacob's memories (and hallucinations) of his son Gabe (Macaulay Culkin, uncredited) and former wife Sarah (Patricia Kalember), and to his present (set in 1975) relationship with a woman named Jezebel (Elizabeth Peña) in New York City. During this latter period, Jacob faces several threats to his life and has severe hallucinatory experiences. It is subsequently revealed that his son Gabe was hit by a car and killed while Jacob was in Vietnam.
At a key moment, Jacob's friend, chiropractor and guardian angel Louis (Danny Aiello), cites the 14th century Christian mystic Meister Eckhart—"Eckhart saw Hell too; he said: 'the only thing that burns in Hell is the part of you that won't let go of life, your memories, your attachments. They burn them all away. But they're not punishing you,' he said. 'They're freeing your soul. So, if you're frightened of dying and... and you're holding on, you'll see devils tearing your life away. But if you've made your peace, then the devils are really angels, freeing you from the earth.'"
As the hallucinations become increasingly bizarre, Jacob learns about chemical experiments performed on U.S. soldiers in Vietnam. His surviving platoon-mates confess to Jacob they too have been seeing horrible hallucinations. Jacob loses an army buddy in a car-ignition explosion while reaching down to pick up a quarter. Jacob is then approached by a man named Michael Newman (Matt Craven), who claims to have been a chemist working with the Army's chemical warfare division in Saigon where he worked on creating a drug that would increase aggression in soldiers. Tests of the drug (code-named "The Ladder" in reference to the effect) were first performed on monkeys and then on a group of enemy POWs with gruesome results. Later, small doses of "The Ladder" were secretly given to Jacob's fellow soldiers via their C-rations. Instead of targeting the enemy, however, the men in Jacob's unit attacked each other indiscriminately. This revelation insinuates that Jacob was stabbed by one of his own men.