Phillip K. Dick’s A Scanner Darkly, first published in 1977, is a dystopian novel that is testament to a time—late ‘60s-early ‘70s—when drug experimentation was a viable alternative to the grown-up world of nine-to-five jobs and suburban family life. Set in a future Southern California (1994), the novel is dedicated to many of Dick’s friends who didn’t survive the experiment or were left with permanent brain damage. Dick’s prolific career includes over 40 novels and several short story collections, notably Do Androids Dream of Electric Sheep?, Minority Report, and The Man in the High Castle. He is considered one of the most important 20th-century science fiction writers. In the 1970s, he began to concern himself with metaphysics and theology, and A Scanner Darkly clearly incorporates both elements. In 2006, the novel was adapted into a film by director Richard Linklater.

Content Warning: This study guide includes discussion of nonconsensual sex, sexual violence, drug use, and mental health conditions related to drug use. The author uses the term “dopers” to refer to those with an addiction to Substance D and contrasts this group with “straights,” or those who don't use drugs. This study guide reproduces these terms to accurately summarize and analyze the source text.

Plot Summary

Jerry Fabin routinely uses the mind-altering drug known as Substance D (“slow death”). He’s convinced his home and body are infested with aphids, and when the paranoia intensifies, he is taken to a New-Path rehabilitation clinic. Meanwhile, undercover narcotics agent Bob Arctor addresses the Orange County Lion’s Club. The official script is filled with boilerplate platitudes about eradicating drugs and prosecuting dealers, but Arctor, who doesn’t buy into the message, deviates, suggesting that users are really victims who deserve empathy. His supervisors order him to stick to the prewritten text. Afterward, he goes undercover by checking himself into a New-Path clinic, searching for a high-profile drug runner who may be hiding there.

Arctor lives in a house with Jim Barris and Ernie Luckman, two users who Arctor hopes will provide intelligence on the manufacturer of Substance D. His other contact is Donna Hawthorne, a small-time dealer to whom he is deeply attracted. He tries to score large amounts of Substance D from her to find out who her source is, but his feelings for her, as well as his own growing addiction, cloud his judgment. One day, Arctor finds his prized “cephalochromoscope” (a device that allows users to see their own brain patterns) damaged, and he suspects Barris, although the motive is unclear. Barris, college-educated with knowledge of electronics and chemistry, professes concern and offers to help Arctor find the suspect, but they abandon their pursuit due to distraction and for the sake of the next score. When Arctor’s car malfunctions on the freeway, he suspects tampering by the same person who damaged his “cephscope.”

Meanwhile, Arctor, who is known to his supervisor as Fred—and whose identity is concealed by his “scramble suit”—monitors the activities in Arctor’s house via a hidden scanner and makes regular reports to his supervisor Hank. At the same time, department psychologists evaluate Arctor for signs of Substance D addiction.

Arctor tries to learn more about Donna, but he hears stories that suggest she may not be who he thinks (Luckman tells tales of her stealing postage stamps and Coke). He grows unsure of his friends’ identities as well as his own. He’s not sure if he’s really Fred observing a suspect named Bob Arctor or if the two are the same. His suspicion of Barris grows when he observes him passively ignoring Luckman, who nearly chokes to death on food. He fears Barris might try to kill Donna. Later, he meets Donna to pick up Substance D, but she doesn’t respond to his romantic overtures. Hurt and angry, he spends the night with Connie, a “needle freak.”

As his observations of the house continue, Arctor’s mania intensifies. When Barris, masquerading as Arctor over the phone, refuses to pay a locksmith bill, it only confirms in Arctor’s mind that Barris has a subversive agenda. Arctor then undergoes another round of psych tests, and the results suggest serious addiction resulting in neurological damage. Hank pulls Arctor off the case and orders him into rehab. Donna drives him to a New-Path clinic where he begins to experience withdrawal. On the way, Donna is revealed to be an undercover agent herself, and she bemoans the fact that Arctor has been used by the agency as a sacrificial lamb in its pursuit of the source of Substance D.

As Arctor endures withdrawal, his mind only processes basic functions—simple tasks and rudimentary language skills. Mike, another recovering addict who is also working as an informant for the agency, befriends him. In time, Arctor is transferred to a New-Path farming facility where he discovers the agricultural source of Substance D: a plant being cultivated and distributed by New-Path. A remnant of his conscious mind takes note of this discovery, resolving to share it with his friends.