In 1939, Universal Pictures premiered the third installment of its Frankenstein trilogy. Like Frankenstein (1931) and Bride of Frankenstein (1935) before it, Son of Frankenstein was a hit with horror-loving moviegoers. Now, the uncut trailer for the classic flick has found a new audience online after being lost for decades, IndieWire reports.

The trailer, originally filmed on flammable nitrate, was shared by YouTube user Jonathan Froes on October 17. It features Bela Lugosi as Ygor, Basil Rathbone as Baron Wolf von Frankenstein, and Boris Karloff reprising his iconic role as the monster. The trailer endures as a piece of cinema history, while providing bonus content for fans: It contains alternate takes and scenes deleted from the final film.

Son of Frankenstein solidified the monster’s franchise potential, and he has been appearing on movie screens ever since. According to Guinness World Records, he’s the second most commonly portrayed character in horror films, right behind Dracula.

[h/t IndieWire]

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