With the strict rule from Edison's Motion Picture Patents Company it was a bit hard for some directors and writers to come up with a story to fit the 10 to 20 minute mark, but even with feature films, there's only so much time you can use to tell your story and sometimes your story might be so long that you have to cut something out to make the movie more suitable for your audiences.

So people like Edison figured, well if I can't fit a whole story into one feature, let's turn this one feature into multiple feature films. These multiple feature films that would continue were the last feature left off would be known as serial films.

These were films that would have a main story or a main plot and that plot would have chapters, sometimes ranging from 12 to 15 to sometimes 20 chapters or even longer and each chapter would have it's own run time, it can be short from 15 mins to as long as about an hour.

These serial films would usually be used for westerns, superheroes, sci-fi, crimes, ect and they were usually cheap films to make, at least during the silent film era, and the plot would mostly be about a hero saving something or someone from the villain and usually they would have what was known as a cliffhanger which was basically like a 'to be continue' type of ending and it would be something like, "Will our hero make it through this trap? Or will the bad guy finally defeat the hero?" And if people wanted to know the ending they would have to wait until the next film to find out.

The earliest known serial film was the Nick Carter detective series released in France in 1908, based on the popular American comic book of the same name, but serial films started to become more popular after the Edison company released What Happened to Mary on July 26, 1912, also based on a popular magazine story of the same name that would also feature cliffhangers at the end of each story. One of Edison's managers, Horace G. Plimpton, was interested with the story and asked the magazine publishers if he could turned these stories into short films and released the films along with the magazine, once it was released it was popular, and helped launch more serial films along the following years, and this serial gained a sequel called Who Will Marry Mary? Released on July 26, 1913.

So throughout the 1910s to the 50s, more serials were released and while some studios would stop making serials films due to the Great Depression causing some studios to filed for bankruptcy because they couldn't transition from silent films to sound films. Other studios, like Republic Pictures, Columbia Pictures, and Universal Pictures transition well into sound films and continue making more serial films, sometimes based on popular superhero comics, like Batman and Superman, but by the time the 50s were here, television was starting to become very popular and almost everyone had a television in their home at some point, so there was no real need to have serial films anymore, so after Blazing the Overland Trail premiered on August 4, 1956, serial films were gone.

Today serial films have been popularized, satirized and even some are still being made with technology. One of the most famous cartoons and shows to satirize serial films were Rocky and Bullwinkle, Danger Island, and Doctor Who. Even some commercials would go the serial film route, like some the cereal commercials or the Cheetos commercials as well. In fact some of the tropes from serial films would carry on to T.V. shows, like the cliffhanger trope and clip shows or in terms of Serial films, recap chapters, which you see in some anime shows.

So while serial films are no longer a thing in terms of movie, there's still some fan made serial films on the internet and while most serial films are lost, the ones that are found are under public domain for anyone to see for free.