With horror cinema of the 1930s and 1940s focusing on monsters and mad scientists, the 1950s saw a shift to more thought-provoking, unsettling horror films. Fears of a nuclear holocaust, foreign invasions, and mutations all made their way into the decade’s horror films. That's not to say that classic themes like monsters were absent, as numerous creature feature movies in the '50s built off of the foundation of the previous decades to deliver some truly iconic characters and stories.

Titles like Invasion of the Body Snatchers and The Fly may have dominated headlines and the box office, but there are lesser-known horror films of this era, a time when independent horror productions thrived, that deserve more recognition. Here are the top underrated horror movies of the 1950s, ranked.

10 Attack of the Giant Leeches

Yvette Vickers in Attack of the Giant Leeches
American International

This low-budget independent film focuses on a local community plagued by giant leeches, but it takes a man being accused of murder to get anyone to take the threat seriously. Once the game warden schedules an investigation in the caves underneath the swamp, he and his team of hunters discover the full scope of the terror that lurks beneath.

It’s amazing how much tension director Bernard Kowalski was able to create with limited resources and a brief running time of just over an hour. Some of the effects and quality may be dated, but the story is captivating and suspenseful. The real success is in the dialogue and the depth given to the characters, even those with relatively little screen time. Any creature feature fan should give Attack of the Giant Leeches a watch.

9 The Screaming Skull

The Screaming Skull 1958
American International

This 1958 independent film is a psychological mind-bender full of suspense and twists. When newlyweds return to the groom's rural mansion, wife Jenni finds herself haunted by unexplained visions and in a constant state of anxiety. She starts seeing a terrifying skull around every corner and must also deal with the gardener, who's always lurking around, giving off a sinister vibe. Are there ghosts locked in the walls, or is this all a product of Jenni's psychosis?

The Screaming Skull may not be hailed as a classic horror film, but its eerie atmosphere and suspenseful story make it a must-see for fans of thrillers with an edge. The black-and-white cinematography, somewhat cheesy effects, and minimalist soundtrack add to the film's eeriness, while the subtle but effective use of sound pulls viewers in and makes them feel like they are part of the story. It's a short production at just over an hour, but it is an excellent little movie that deserves more recognition.

8 Attack of the Crab Monsters

Attack of the Crab Monster movie
Allied Artists

Another low-budget independent film, Attack of the Crab Monsters, is a fun movie about a group of scientists who travel to a remote island in the South Pacific to investigate strange occurrences after a research team goes missing. Once they arrive, it's clear that the nuclear bomb crashing near the island mutated the local crabs, causing them to grow to massive sizes and exhibit human-like behavior.

Related: Best 1950s Horror Movies From AmericaThe effects may be dated, but the movie offers great campy fun. Fans of classic monster films will find a lot to love here, and the story's goofy but endearing blend of science fiction and horror elements make it an easy watch. While it isn't as suspenseful or atmospheric as some of the other titles on this list, it's an enjoyable movie that's definitely worth checking out.

7 The Undead

The horror movie The Undead from 1957
American International

If you're looking for an eclectic movie that encompasses elements from nearly every genre while remaining ahead of its time, The Undead is a must-see. Directed by Roger Corman in 1957, this film tells the story of a prostitute that is sent back to a past life by two psychic researchers. The problem is that in the 15th century, she's believed to be a witch, and is scheduled to be executed the very next morning. What ensues is the development of diverse characters like the Gravedigger and Satan, who provide the much-needed theatrical moments throughout the movie.

The Undead is an ambitious and creative film that manages to be just campy enough to be entertaining. It's not a perfect production, but much of the charm lies in its down-to-earth aesthetic, making it a fun watch overall.

6 The Man Without a Body

The Man Without a Body 1957
Budd Rogers Releasing

The Man Without a Body (sometimes credited as Curse of Nostradamus) is a fantastic horror sci-fi thriller released in 1957. Directed by Charles Saunders and W. Lee Wilder, this film follows the story of a wealthy man who, after learning he has a brain tumor, turns to a mad scientist who transplants monkey heads onto different bodies for help. They rob the head of a Nostradamus from his tomb with the intention of transplanting it onto the wealthy man's body.

This movie is an overlooked gem, though some consider it to be a cult classic in the genre. Some find the jumbled and inventive plot to be a bit of a mess, but it's the absurd creativity of the movie that makes it a one-of-a-kind film.

5 The Abominable Snowman of the Himalayas

The Abominable Snowman of the Himalayas
20th Century Fox

This 1957 British-American horror fantasy film, directed by Val Guest, follows a group of scientists as they journey to the Himalayan Mountains in search of the mythical Yeti. The thriller is a combination of horror, science fiction, and adventure, though it may not appeal to all fans of the genre. The story is somewhat of a slow build, allowing viewers to learn about differences between the men, as well as the fictional and real-world portrayals of the Yeti.

One of the best elements of The Abominable Snowman of the Himalayas is the snowy, isolated setting. It gives the movie a haunting ambiance and adds to the suspenseful nature of the film. The moment when the scientists finally encounter the Yeti is also quite effective and offers a great payoff for viewers. It's an underrated watch that deserves more recognition.

4 It Came From Beneath the Sea

Monster from It Came From Beneath the Sea
Columbia Pictures

This 1955 science fiction horror classic, directed by Robert Gordon, follows the story of a giant octopus that has been mutated by atomic testing and is now terrorizing the Pacific Coast. Another great example of cold war-era science fiction, It Came From Beneath The Sea, offers creative monster carnage and plenty of campy moments. It takes a bit to get to the action, but the last half of the movie makes the watch worth it.

Related: The Most Underrated Horror Movies of All TimeWhat makes this one stand out from other monster movies of the era is its use of a larger-than-life creature combined with some surprisingly good visual effects. Looking at monster movies today, it's easy to forget how advanced these effects were back in the 1950s. It Came From Beneath The Sea is a great choice for those seeking an entertaining watch.

3 The Angry Red Planet

The Angry Red Planet 1959
American International

The Angry Red Planet, also titled Invasion of Mars and Journey to Planet Four, is an underrated science fiction horror classic from 1959. After a spaceship sent to explore Mars is presumed to be missing, it is surprisingly located and brought back to earth with just two survivors. One is suffering from amnesia and unable to remember the events that happened on the red planet. Doctors try and help him recover his memory, but it quickly becomes clear how dangerous the mission was.

Many praise the fun atmosphere of this movie, specifically the red tinting of all the scenes that take place on Mars. The movie plays out more like a B-movie, with its over-the-top acting and campy dialogue, but it still works as a thrilling sci-fi piece. It takes no time for the action to kick in, and it is great for those who love monster films with a touch of humor.

2 Macabre

Christine White in Macabre
Allied Artists

Macabre is an incredibly underrated horror movie by legancy cult director William Castle that was first released in 1958. It's a revenge thriller set in a small town with a dark and gritty atmosphere. It follows a doctor, Dr. Rodney Barrett, who learns his daughter is in grave danger. She's been abducted and buried alive, and he has just hours to locate her before she succumbs to a horrible fate. Though this is different from Castle's other well-known films like House on Haunted Hill, Macabre is a classic in its own right.

When the film first debuted, it was deemed too extreme for some theater-goers. Castle used this to his advantage and provided insurance on each ticket bought. If anyone died of fright during the movie, their families would be given $1,000. Though this gimmick was merely a marketing ploy, Macabre is still a thrilling watch that should be part of any horror fan's collection.

1 The Black Sleep

The Black Sleep horror movie
United Artists

The 1956 classic The Black Sleep is a unique take on the horror genre. It follows a doctor, Dr. Cadman, who is trying to find a cure for his wife's terminal brain tumor. He's so desperate that he turns to a former student on death row and uses a serum that can induce a "black sleep" in humans to get him out of the prison and to his estate to help him with his experiments. What follows is a suspenseful journey filled with dark secrets and gothic horror elements that make this an instant classic.

The cast really helps to elevate this movie, which includes horror legends such as Basil Rathbone, Lon Chaney Jr., and Bela Lugosi in one of his last roles before his death. It has all the right ingredients for an excellent horror flick, and it's definitely one of the best from its time period. The creativity of the storyline and use of science-fiction elements make The Black Sleep one of the most memorable but underrated horror movies of the 1950s.