I began the Dark Tower novels when I was in high school and finished them in college. I have always been a Stephen King fan, so obviously I discovered the series. This series is definitely Stephen King's best work. Roland Deschain, the last Gunslinger, is left with the burden of saving the world by reaching the Dark Tower before the Man in Black. In the second novel, The Drawing of the Three, he finds his three apprentices, Susannah, Eddie, and Jake. Now that his ka-tet is complete, they begin their journey to save the world. One of the major elements of the novels is time travel, to this world and other worlds. Roland and his ka-tet travel to other wheres and whens throughout the novels. King even creates his own language, High Speech, which is used by the characters they encounter in Roland's world. One of my favorite aspects of the series is that Stephen King incorporates some of his other novels and even events from his own life into the series. Here's a list of his other short stories and books that are connected to the Dark Tower series: 'Salem's Lot, The Stand, The Eyes of the Dragon, The Talisman, Black House, It, Insomnia, Regulators, Desperation, Rose Madder, Bag of Bones, From A Buick 8, Skeleton Crew, Hearts in Atlantis, Everything's Eventual, and Little Sisters of Eluria.
This is the list of the novels in the Dark Tower series:
The Gunslinger, The Drawing of the Three, The Wastelands, Wizard and Glass, Wolves of the Calla, Song of Susannah, The Dark Tower