The Magic Tree House series is coming to the big screen.

Lionsgate has acquired the rights to all 54 books in Mary Pope Osborne’s children’s series, and the studio has already started work on the first live-action film in a planned series.

Osborne’s beloved novels, which have sold more than 130 million copies, follow the adventures of brother and sister Jack and Annie as they discover an enigmatic book-filled tree house that has the power to send them through time and space.

Osborne is serving as executive producer with her husband, Will, who has written the first script with Chicago playwright Jenny Laird. The first film is based primarily on the 29th book, Christmas in Camelot, which finds Jack and Annie rediscovering the tree house after having outgrown it. There, they find themselves summoned to Camelot, where they must become its saviors.

“Lionsgate has an impressive reputation for working closely with content creators, respecting and protecting their vision, and making them part of the creative process,” Osborne said in a release. “I’m thrilled to have partnered with them on bringing the Magic Tree House books to life in a series of films that kids, parents and grandparents will all get to enjoy together.”

Lionsgate has a history of acquiring book series for children and young adults, and the studio previously adapted the Hunger Games franchise and the first two installments in the Divergent series.