The Saw franchise has just crossed a major milestone. Thanks to the success of Spiral: From the Book of Saw, the long-running horror series has crossed the $1 billion mark at the global box office. This puts the movies in relatively rare air as few horror franchises in history have ever managed to amass that kind of money. It also all but ensures that the series will continue in some way, shape or form beyond this most recent entry.

Spiral won its second weekend at the box office, pulling in $4.5 million domestically and $2.67 million from overseas markets. All told, the movie, which stars Chris Rock and Samuel L. Jackson, has earned $22.5 million to date. That has pushed the Saw franchise, overall, to $1,000,799,533. The series consists of nine entries released over the last 17 years. David Spitz, Lionsgate's president of domestic theatrical distribution, had this to say about it.

"We congratulate our friends at Twisted Pictures and all of the filmmakers and stars who have been a part of the Saw legacy. Over the years, our partners have been innovative, creative, and open to new ideas as they have nurtured a micro-budget film into a billion-dollar-plus-grossing cultural phenomenon."

While entries from franchises like The Avengers, Star Wars and The Fast and the Furious regularly make more than $1 billion with a single movie at theaters, they cost hundreds of millions to make. What has made Saw so financially successful for Lionsgate is that these movies are remarkably cheap to produce, relative to what they bring in at the box office. In Hollywood, it's all relative, and in that game of relativity, these movies have delivered in a big way.

Tobin Bell led many of the entries as John Kramer, aka Jigsaw. The man wanted to inspire bad people to live better lives, and did so through bloody, torturous means. Generally speaking, the movies feature people having to escape elaborate traps, often at great cost.

The original Saw was released in 2004. Directed by James Wan and written by Leigh Whannell, who also starred, it became a huge hit. Working from a budget of just over $1 million, it earned $103.8 million globally. That paved the way for a series of sequels, which began in 2005 with Saw II. The series reached its highest point in 2006 with Saw III, which earned $163.8 million. The lowest-grossing entry was Saw VI, which earned just $69.7 million. But every single entry has been successful. The most expensive one to make, 2010's Saw 3D, was still produced for just $17 million, earning $133.7 million during its theatrical run.

Darren Lynn Bousman is largely responsible for the franchise's box office success, as he directed Saw II, Saw III, Saw IV and Spiral. As for the future, Saw 10 is already said to be in development, though plot details remain under wraps for the time being. Lionsgate and Twisted Pictures are also working on a potential Saw TV series, though details are also scarce on that front currently. This news was previously reported by Variety.