Donald "Donny" Kohler is obsessed with fire and human combustion, an obsession that stems from the severe abuse he suffered at the hands of his mother, who would hold his bare arms over a gas stove in an effort to "burn the evil out of him". When his mother dies, he sets out to avenge himself on every woman who bears a resemblance to her with the aid of steel chains, a flamethrower, and a steel-paneled bedroom crematorium.
Donny's first victim is florist Kathy Jordan (Johanna Brushay). Befriending the harmless-looking man, Kathy escorts Donny back to his mother's house, where he knocks her unconscious, strips her naked, and chains her arms and legs to the ceiling and floor of the steel room. Ignoring Kathy's screaming pleas for mercy, he burns her to death with his flamethrower. Over the next few days, Donny murders two other women by immolating them. Donny also burns his mother's corpse, and dresses it up in her bedroom along with the other three dead women.
During his killing spree, Donny hears voices in his mind which call him "the master of the flame" and urge him to punish "evil". Donny's only friend is Bobby Tuttle (Robert Osth) a co-worker who phones the house one day asking why Donny has been absent from work for nearly a week. Donny lies and claims that his mother is sick and needs attention. When Donny attempts to pick up another victim, he cannot go through with it, and begins to feel remorse for his actions. Donny goes to a church, where he tells Father Gerritty (Ralph D. Bowman) about the abuse his mother inflicted upon him, and about his urges to kill. Father Gerritty persuades Donny to try to move on with his life, and put the past to rest.
In an attempt to stop killing, Donny decides to accept an invitation by Bobby to accompany him on a double-date to a disco club, despite Donny's lack of social skills. After traveling to a men's clothing store and purchasing a new outfit, Donny shows up at the disco as expected, but is shy and awkward with his date. When the woman attempts to take Donny to the dance floor and inadvertently holds his arm over a table's lighted candle, the memories of the childhood abuse come back, and Donny sets her hair on fire.
Fleeing from the disco, Donny runs into two drunken girls on the street, and he invites them back to his house. Bobby attempts to find Donny, and runs into Father Gerritty on his way to Donny's house. When no one answers the front door, Bobby and Father Gerrity break it down and rescue the two women. Donny dons his incinerator outfit and sets Father Gerrity ablaze with his flamethrower, but Bobby manages to smother the flames and rescue the priest.
Donny takes refuge inside his mother's bedroom with the burned corpses. The voices in his head express their disappointment with him. Donny hallucinates the charred corpses coming to life. He tries to fight them with the flamethrower but sets the house on fire. He dies in the fire.
The final scene portrays a young boy being beaten by his mother. The boy hears the same whispering voices that Donny did, and they tell him that they are here to "help" him.Dan Grimaldi as Donald 'Donny' Kohler
Colin Mclnness as Young Donald Kohler
Charlie Bonet as Ben
Bill Ricci as Vito
Robert Osth as Bobby Tuttle
Ruth Dardick as Mrs. Kohler
Ralph D. Bowman as Father Gerritty
Joey Petzel as Bobby Tutle's son
DVD Talk gave Don't Go in the house a three and a half out of five, writing that, Don't Go in the House "is one of those rare films that works really well despite the fact that rips off better known movies" and "it's a bitter, ugly, and nasty little horror movie that doesn't pull any punches and is just as seedy today as it was when it was made. It's effective in that it gets under your skin despite its low budget origins and obvious flaws". Hysteria Lives! gave the film the same rating, writing, "Grim is the only word for Joseph Ellison's psychological terror movie" and "It's easy to forget just how nihilistic much of American genre cinema was as the 70s turned into the 80s (especially with the avalanche of cheese that was just round the corner), but Don't Go in the House is a chilly reminder of times when practically anything went".
DVD Verdict also had a positive response, writing "Don't Go in the House is a well-acted, disturbing film" and "this movie is a mental and visual screw job. Writer/director Joseph Ellison has put together a brutal little 'psycho' flick—part excursion into the tortured mind of an abuse victim, and part shock horror". Retro Slashers found Don't Go in the House a "very dull" piece that was brought down by bad acting, and a lack of suspense and originality.
Despite some respectable critical notices, Don't Go in the House attracted controversy almost immediately because of its graphic depiction of the death of Kohler's first victim, and the central theme of childhood abuse. The film was cut by almost three minutes when it was released in Britain in the winter of 1980, but an uncut version was released on video by the Arcade label in 1982 – knowingly or not, they advertised the release as "a true 'nasty' from Arcade", and it quickly wound up on the DPP's list of banned titles. The pre-cut British cinema version was released on video by the Apex label in April 1987, though the film was finally passed uncut in 2011.
Shriek Show's region 1 DVD presented a remastered widescreen print of the film with an audio commentary from star Dan Grimaldi, as well as a filmed interview with Grimaldi, theatrical trailers, TV spots, and short "unmatted" extracts from the full-screen VHS version.
The film was also released uncut on DVD in the UK for the first time in 2012 by Arrow Films. This release was a remastered print with a reversible cover and special collector's booklet.