According to Wes Craven, the film was severely cut for an R-rating. It took around 13 submissions to the MPAA to receive an R instead of an X rating. Some of the scenes that were cut include: Pinker spitting out fingers that he bit off from prison guard, longer and more graphic electrocution of Pinker, and longer scene of possessed coach stabbing his own hand.
Originally envisioned as a series, in the vein of Wes Craven's "A Nightmare on Elm Street (1984)," but after the lukewarm box office reception, the idea was dropped.
The body of the jogger in the park that Horace takes over is Jonathan Craven, son of director Wes Craven.
The body of the male road worker with long black hair that Horace takes over is former guitarist for Alice Cooper, Kane Roberts.
When shooting the scene where Jonathan wades into the lake, Peter Berg suffered from hypothermia due to the extreme cold temperatures.
Wes Craven allegedly conceived the story, as well as the character of Horace Pinker, as a response to the diminishing quality of the sequels to A Nightmare on Elm Street (1984). Craven had a hand in writing and producing A Nightmare on Elm Street 3: Dream Warriors (1987), which he saw as his way of finishing that series.
Alive Films took the rights to the film when fellow horror director and friend John Carpenter bowed out of his four-film deal with the production company after making They Live (1988), offering the remaining slots in his contract to Wes Craven. As a result, Craven's next two projects, Shocker and The People Under the Stairs (1991), were financed by Alive.
Shocker was filmed in ten weeks and on a low budget. Wes Craven said that this was achieved by having a small crew and little known actors.
Was the last film to be released on videocassette under the MCA Home Video banner before the name was changed to MCA/Universal Home Video.
Mitch Pileggi appeared in character as Horace Pinker to promote the film on a special Halloween episode of MTV's Headbangers Ball (1987).
According to an article in Fangoria magazine, Wes Craven first pitched the concept as a television series to Fox. Craven later crossed over to TV with the short-lived NBC series Nightmare Cafe (1992).
The last of a cycle of horror films about murderers coming back from the dead after execution in the electric chair. Prison (1987), Destroyer (1988), and The Horror Show (1989) preceded it.
When Jonathan and his father enter the Tavern after the funeral of their family, a news program is playing on the TV in the background and discussing the murders. Someone immediately changes the channel and on comes (briefly) the 1986 concert footage of Alice Cooper's The Nightmare Returns tour.
Heather Langenkamp had a brief appearance as a victim in this film. She had previously started as Nancy Thompson, the main protagonist, in A Nightmare On Elm Street. Both of these films were written and directed by Wes Craven.