We get frustrated with Hollywood's propensity for weird sequels that seem to have little or nothing to do with the original, but it just so happens that the practice is older than filmmaking itself. Several classic stories have strange follow-ups you've never heard of, like...

1. The Starlight Barking

In case you're unaware, Disney's 101 Dalmatians was actually based on a novel, The Hundred and One Dalmatians, by Dodie Smith. You may also be further unaware that Smith wrote her own sequel that Disney ignored, titled The Starlight Barking.

Instead of just being a rehash of the original, Smith's story takes a very bizarre turn and involves all the world's dogs finding every living thing besides themselves in a form of stasis caused by a dog-like alien named Sirius, who invites them all to abandon Earth and join him on the Dog Star.

2. The Giver Trilogy

An extremely popular book for middle school students, Lois Lowry's The Giver has become an instant classic in the 20 years since its publication. Countless children have been assigned essays about how they interpreted the book's ambiguous ending, but they could have saved some time and just read the book's two (with a third on the way) sequels instead.

The first sequel, Gathering Blue, is only tangentially related to The Giver by being set in the same universe. However, the following book, Messenger, ties the two together and features the return of Jonas, the main character from The Giver, who obviously did not freeze to death at the end of that book.

3. The Book of the Green Planet

Although Steven Spielberg had every intention of creating a sequel to 1982's movie E.T. The Extra-Terrestrial, things never really came together for it, and now, 30 years later, it looks extremely unlikely that it will ever see the light of day. Unless you read the semi-official novelized sequel, that is.

William Kotzwinkle, who wrote the novelization of the original film, published The Book of the Green Planet in 1985. In it, E.T. returns to his home planet of Vomestra, where he's punished for his trip to Earth and, thanks to a telepathic link, finds that Elliot has begun to grow up and forget the lessons learned from their time together.

4. Little Men & Jo's Boys

Louisa May Alcott's classic, Little Women, is actually already two books in the first place, with the first volume being Little Women and the second being Good Wives, but since they're usually compiled anyway, that hardly counts as a sequel. Luckily for this list, Alcott also produced two actual sequels, Little Men and Jo's Boys.

Little Men revolves around a group of young orphans who are students at a school run by two characters from Little Women, Jo March and her husband, Professor Friedrich. Jo's Boys, a direct sequel to Little Men, features the orphans as adults and shows how their lives changed as a result of interacting with the March family.

5. Closing Time

Joseph Heller's Catch-22 was one of the most popular novels of the 20th century, so much so that it even spawned the term "catch-22" as an everyday phrase. But what's not so popular is the book's sequel, Closing Time, published more than 30 years later. Since the original book was about World War II, long over by that time and not as ingrained into the cultural consciousness as it had been, Heller instead sets the sequel in '90s-era New York City, showing how various characters from the original novel deal with the difficulties of old age and their own mortality.

6. Paradise Regained

Whether you've read it or not, John Milton's Paradise Lost is one of the most influential works ever created. In fact, Milton's poem is responsible for a large percentage of common misconceptions regarding the contents of the Bible, meaning that it not only changed the face of English literature, but Western religion as well.

What failed to make nearly so much of a splash is Milton's follow-up poem, Paradise Regained, which was published in 1671, four years after Paradise Lost. As opposed to the original's 12 books, Regained is a mere four. It tells the story of Jesus' temptation by Satan as seen in the Book of Luke, but the poem never really caught on like the original and is widely unknown today.

7. The Tom Sawyer Series

Mark Twain's The Adventures of Tom Sawyer is one of the most read books in America today, and it's not exactly a secret that Twain later had Sawyer return in The Adventures of Huckleberry Finn. But these weren't the only two adventures the boys had. Twain actually published two other novels in the series, both more than a decade later.

The first, Tom Sawyer Abroad, features Huck, Tom, and Jim attempting to cross the ocean in a hot air balloon while facing numerous hurdles along the way. After that came Tom Sawyer, Detective, which has Tom and Huck attempting to solve a mystery involving stolen diamonds and a possible murder. Further, Twain had three incomplete Tom Sawyer novels--Huck Finn and Tom Sawyer Among the Indians, Schoolhouse Hill, and Tom Sawyer's Conspiracy, the last of which was very nearly completed.

8. The Gone With the Wind Sequels

Margaret Mitchell's beloved Southern romance was not only one of the most famous books of the last century, but also spawned one of the most popular films to boot. Oddly, it took nearly 60 years for people to try to wring more cash out of it.

The book has four sequels, with varying levels of authenticity. The first, Scarlett, was an authorized sequel by Alexandra Ripley and was widely panned. A second that ignores Scarlett, Rhett Butler's People, is a re-telling of the original novel from Butler's point of view by author Donald McCraig.

Then there are the unauthorized sequels: The Wind Done Gone by Alice Randall is a satirical re-telling from the perspective of an O'Hara family slave. Finally, The Winds of Tara by Katherine Pinotti is a direct sequel to the original that the Mitchell family legally blocked from publication in America.

9. The Second Jungle Book

Rudyard Kipling's The Jungle Book is as famous for its Disney animated adaptation as it is for its common usage in elementary school curricula. The book, which is actually just a series of tangentially related short stories, is one of the most well-known and popular in the English language today.

A year after The Jungle Book's release, Kipling wrote a follow-up book called The Second Jungle Book, featuring five further adventures of Mowgli and his friends. Although Disney made an animated Jungle Book 2 and a live-action film called The Second Jungle Book: Mowgli and Baloo, neither actually follows the plot of The Second Jungle Book.

10. The Last Ringbearer

J.R.R. Tolkien's sprawling Middle Earth series covers more than a dozen books, several of which were published after his death. Of all of his extant materials, however, one culture's history is mostly ignored--that of the people of Mordor. True, they're the bad guys, but shouldn't they get a say?

That's the premise behind Russian author Kirill Yeskov's unauthorized sequel, The Last Ringbearer. While it's not an official sequel, the book is actually fairly popular on its own merits. Yeskov presents Mordor as a highly advanced society based around science and technology. Not unlike Gregory Maguire's Wicked, The Last Ringbearer argues that "history is written by the winners" and that Mordor was actually a victim of the primitive cultures of men who blindly followed the Luddite-esque Gandalf.

11. The Amityville Saga

You probably knew from the various films' advertising campaigns that The Amityville Horror was based on a true story. How much is true is, naturally, a matter of contention. But, while the first film (and its remake) was based on the purported experiences of George and Kathy Lutz and the second film was loosely based on the actual DeFeo murders that occurred in the house, all the rest of the films are wholly fictional.

The Amityville books, however, tell a different tale. The Lutz family claimed that their paranormal experiences didn't end when they left 112 Ocean Avenue. According to The Amityville Horror Part II, the demonic forces continued to plague them at Kathy's mother's house. A second sequel, Amityville: The Final Chapter, that also claims to be true, says that the haunting even followed them to California. Other books followed, some even featuring the Lutz family, but all were acknowledged as fictional.