The actual Blob, a mixture of red dye and silicone, has never dried out and is still kept in the original five-gallon pail in which it was shipped to the production company in 1958 from Union Carbide. It was put on display over the years as a part of the annual Blobfest, held over a three-day period each summer in Phoenixville, PA, which provided a number of the shooting locales for the film. In addition to displaying the Blob and miniatures used in the shooting, the event features a reenactment of the famous scene in which panicked theatergoers rush to exit the town's still-functioning Colonial Theater, as well as several showings of the film.

Steve McQueen had the poster of this film on his bedroom wall at the time of his death.

Steve McQueen was playing a teenage high-school student, but he was actually 27 years old.

Steve McQueen was offered $2,500 or 10% of the profits. He took the $2,500 because the film wasn't expected to make much. It ended up grossing over $4 million. According to producer Jack H. Harris when being interviewed by film historian Tom Weaver, the film ultimately grossed $40 million.

The strange movie being shown in the theater was not a phony created for this film. It was an actual movie originally released as Dementia (1955). The scenes shown are from the re-cut version titled "Daughter of Horror", which had narration added. The voice doing the narration is that of Ed McMahon.

According to producer Jack H. Harris, they added dye to the Blob to make it increasingly redder after it had consumed successive victims.

The popular title song that was used over the opening credits was credited to the Five Blobs. There was only one Blob, studio singer Bernie Knee, whose vocals were recorded five times.

In an attempt to profit from Steve McQueen's success in The Towering Inferno (1974), this film was re-released in various countries during the mid-'70s, falsely promoted as an Irwin Allen-style new disaster movie.

Dick Powell, who was the head of Four Star Productions, asked to see a rough cut of this film. This led to the casting of Steve McQueen in the television series Wanted: Dead or Alive (1958).

The movie poster just outside the theater of "The Vampire and The Robot" is actually for "Forbidden Planet", with different titles pasted over the original info.

According to producer Jack H. Harris, Aneta Corsaut was interviewed and hired only two days before shooting started.

The old man's cabin and the crater were filmed in a soundstage. There were two versions of the cabin built. One was full size for the actors to use. The second version was only about three feet high and was used in the background of wide shots to create a false perspective.

Partially filmed in Phoenixville, Pennsylvania. The theater everyone is seen running from is the Colonial Theater.

After the Blob had consumed the old man, the doctor tells his nurse to dump some "trichloracetic acid" on the it. That is a weak acid used to treat genital warts.

This film was originally going to be called "The Glob." It was changed when it was discovered that cartoonist Walt Kelly had already used that title. According to producer Jack H. Harris, the film was titled "The Molten Meteor" when it was in synopsis form.

The Blob was created with a modified weather balloon in the early shots, and in the later shots with colored silicone gel.

The title song "The Blob" was co-written by Burt Bacharach and is on his album "Look of Love:The Burt Bacharach Collection." Paramount tapped Bacharach and Mack David (brother of Bacharach's usual writing partner, Hal David) to come up with a non-threatening theme that would prevent the faint of heart from going into nostril-flaring terror during the opening credits. Together they came up with "The Blob," a goofy musical creature that is one part "Temptation" to two parts "Tequila." Session singer Bernie Knee does the champagne-cork-popping honors by pulling his finger out of his cheek seven times. Only Ralph Carmichael's score received a screen credit, giving credence to the notion that the song was a last-minute addition. The Five Blobs turned out to be a phantom group that consisted of Bacharach, a bunch of musicians for hire and Nee, who tracked his voice five times to achieve that Boris Karloff-esque quality.

The last time Steve McQueen was billed as Steven.

Final film of Olin Howland (the farmer who is the first victim of "The Blob").

In changing the title from "The Glob" to "The Blob," producer Jack H. Harris has hoped that comedians would still pick up on it. As he predicted, many comedians mentioned "The Blob" during their routines. This resulted in this low budget movie getting many free plugs on national television.

Film debut of Aneta Corsaut.

The monster is referred to as "the mass" in the shooting script.

Although producer Jack H. Harris always claimed that this film cost $240,000 to produce, years later director Irvin S. Yeaworth Jr. said that the actual cost was only $120,000. Other sources list the budget as low as $110,000.

When Steve and Jane go to the police station to report the death of Dr. Hallen, the calendar on the wall reveals that it is July 1957.

This independent production was originally picked up by Paramount Pictures for use on the bottom half of a double bill with Paramount's production, I Married a Monster from Outer Space (1958). Early marketing tests and initial bookings indicated that a larger share of the ticket buyers were coming for this film rather than the top-billed picture, so it became the main feature and more money was spent on its promotion.

The credits list this as a "Tonylyn Production." This was actually a combination of the names of producer Jack H. Harris' two children, Tony and Lynda.

McQueen' s car in the movie is a 1953 Plymouth Cranbrook blue convertible.

Jack H. Harris' personal favorite of all his films.

According to producer Jack H. Harris, director Irvin S. Yeaworth Jr. initially met Steve McQueen when the actor's wife Neile Adams was appearing in a short religious film Yeaworth was making. According to Harris, Yeaworth found McQueen to be "a dirty jerk, an opinionated pain in the ass," among other things, and reportedly kicked him off of the set after Adams' part was completed. Hopeful of signing 'Anthony Franciosa' for the lead in "The Blob," Harris attended a performance of "A Hatful of Rain" in which Franciosa was appearing, but when he saw understudy McQueen filling in for an ailing Ben Gazzara, the producer decided to sign McQueen to a three-picture deal. McQueen proved so difficult that rather than find an entirely new director and crew to work with him, Harris decided to shoot the two subsequent films, The Evil Force (1959) and Dinosaurus! (1960), with other actors, a decision he ultimately regretted.

Bart Sloane is credited for special effects. He also served as the art director and animator. He created the animated sequence and main title over which the cast and credits were matted. His other animated sequences included the shot of the electric cable being shot off of the pole and the live electric line striking the blob. He also created the matte paintings.

Aneta Corsaut's name is misspelled "Aneta Corseaut."

In some of the promo material, the character played by Aneta Corsaut is referred to as Judy. Her character in the film is named Jane.

According to producer Jack H. Harris, there were at least two proposed television series based on this film. None had made it to the pilot stage. Harris jokingly suggested that The Blob could become a good guy and solve crimes.

Steve McQueen constantly smoked cigarettes during filming even though he is never shown smoking in the movie. At about 49 minutes into the movie you will notice smoke coming up behind Steve. That's because he is holding a lit cigarette behind him with his hand behind his back.

There's a scene where the Blob goes to the diner down the street from the theater. In reality, the two are 11 miles apart from each other.

Veteran actor Olin Howland is listed in the credits as "Olin Howlin"

Producer Jack H. Harris was also a producer on this film's 1988 remake.

Producer Jack H. Harris had experience as a distributor, but this was his first foray into motion picture production.

When Officer Richie tunes the radio and keys the microphone to give his chess move, there is clearly no cable connected to the microphone head.

When the doctor is being consumed by the Blob there is actually more footage of his death that's been cut out, as it was considered too violent at the time of movie's release.

The building they enter to get the fire extinguishers is the Samuel K Barkley Elementary School in Phoenixville PA.

When the blob first appears it is blue then it's clear and finally red.

The name Steve is said 50 times during the movie.

The 80 cents movie ticket is equal to $7.00 in 2018.

Russell S. Doughten Jr., who also directed The Blob, only worked on Christian films. He felt there was a message being said to support teenagers in this movie.

The firemen and a fire truck in the movie were from the Alert fire company in Saint Clair, Schuykill County, PA

This film is part of the Criterion Collection, spine #91.