In the small New England town of Dunwich, a priest commits suicide by hanging himself in the church cemetery which somehow opens the gates of hell allowing the dead to rise. Peter, a New York City reporter, teams up with a young psychic, named Mary, to travel to the town where they team up with another couple, psychiatrist Jerry and patient Sandra, to find a way to close the gates before All Saints Day or the dead all over the world will rise up and kill the living.

In Louisiana, the thirty-five year old single mother Lavina delivers a baby boy and a monster in the evil Whateley House. Ten years later, Dr. Henry Armitage and his assistant Professor Fay Morgan discover that the page 751 of every copy of the Necronomicon is missing and The Black Brotherhood has summoned the gate keeper Yog Sothoth to leave the portal opened to the demons and ancient gods. They invite the arrogant and skeptical Professor Walter Rice that can translate the Necronomicon to help them to seek the book. Meanwhile Lavina's son Wilbur Whateley ages very fast and seeks the missing page to open the portal.

Ramon the alligator is flushed down the toilet as a baby and grows into a gargantuan monster by eating the corpses of laboratory animals who have undergone dubious hormone experiments, thus providing all the ecological and social subtext that one could possibly wish for, even if one doesn't normally go for films about giant alligators eating people left, right, and center--which is the inevitable and tragic result of Ramon's decision that the outside world looks rather more interesting than the sewers....

After Jonathan Harker attacks Dracula at his castle (apparently somewhere in Germany), the vampire travels to a nearby city, where he preys on the family of Harker's fiancée. The only one who may be able to protect them is Dr. van Helsing, Harker's friend and fellow-student of vampires, who is determined to destroy Dracula, whatever the cost.

Strange things are happening in Riverdale, Illinois. A huge, seemingly alien structure has been found jutting out of the earth. Sent to investigate the origin of the mysterious object, Senator Walter Powers discovers that parasites from the center of the earth have infiltrated the town, taking control of the authorities and workers, making communication with the outside world impossible, and leaving the responsibility of stopping the invasion up to Powers and a small group of free individuals.

Three tales of terror: in "The Graveyard Rats" lovers murder the woman's older husband and encounter horror when they attempt to rob his grave; "Bobby" is the story of a woman who summons her son back from the dead; and in "He Who Kills" an African doll goes on a murderous rampage.

In prison and awaiting execution, Dr. Victor Frankenstein recounts to a priest what led him to his current circumstance. He inherited his family's wealth after the death of his mother when he was still only a young man. He hired Paul Krempe as his tutor and he immediately developed an interest in medical science. After several years, he and Krempe became equals and he developed an interest in the origins and nature of life. After successfully re-animating a dead dog, Victor sets about constructing a man using body parts he acquires for the purpose including the hands of a pianist and the brain of a renowned scholar. As Frankenstein's excesses continue to grow, Krempe is not only repulsed by what his friend has done but is concerned for the safety of the beautiful Elizabeth, Victor's cousin and fiancée who has come to live with them. His experiments lead to tragedy and his eventual demise.