The House of Frankenstein

The House of Frankenstein is a 1944 American monster crossover horror film starring Boris Karloff and Lon Chaney Jr., directed by Erle C. Kenton, written by Curt Siodmak, and produced by Universal Studios as a sequel to Frankenstein Meets the Wolf Man and Son of Dracula the previous year. The cast includes a mad scientist (Karloff), the Wolf Man (Chaney), Count Dracula (John Carradine), a hunchback (J. Carrol Naish), and Frankenstein's monster (Glenn Strange). This "monster rally" approach would continue in the following film, House of Dracula, as well as the 1948 comedy Abbott and Costello Meet Frankenstein.

Plot
Dr. Gustav Niemann (Boris Karloff) escapes from prison along with his hunchbacked assistant Daniel (J. Carrol Naish), for whom he promises to create a new, beautiful body. The two murder Professor Lampini (George Zucco), a traveling showman, and take over his horror exhibit. To exact revenge on Bürgermeister Hussman (Sig Ruman), who had put him in prison, Niemann revives Count Dracula (John Carradine). Dracula seduces Hussmann's granddaughter-in-law Rita (Anne Gwynne) and kills Hussmann himself, but in a subsequent chase, Niemann disposes of Dracula's coffin, causing the vampire to perish in the sunlight.

Niemann and Daniel move on to the flooded ruins of Castle Frankenstein, where they find the bodies of Frankenstein's monster (Glenn Strange) and Lawrence Talbot, the Wolf Man (Lon Chaney Jr.), preserved in the frozen castle. Niemann thaws them and promises to find Talbot a cure for the curse. However, he is more interested in reviving the monster and exacting revenge on two traitorous former associates than in keeping his promises. Talbot transforms into a werewolf and kills a man, sending the villagers into a panic.

Niemann and Daniel save a gypsy girl named Ilonka (Elena Verdugo), and Daniel falls in love with her; it is unrequited, however, as Ilonka falls in love with Talbot. Daniel tells Ilonka that Talbot is a werewolf, but she is undeterred, and promises Talbot that she will help him.

Events reach a crisis point when Niemann revives the monster and Talbot again turns into a werewolf. The werewolf attacks and fatally wounds Illonka, but she manages to shoot and kill Talbot with a silver bullet before she dies. Daniel blames Niemann and turns on him. The monster intervenes, throws Daniel out of the window, and carries the half-conscious Niemann outside, where the villagers chase them into the marshes. There, both the monster and Niemann drown in quicksand.