In my freshman year of college, I learned that a kid down the hall had never seen Star Wars. None of it. He had actually never heard of Luke Skywalker or Darth Vader or R2-D2 — I don’t know how; he seemed normal enough. Once my roommates and I overcame our shock, we plopped him down in our common room for a marathon viewing: A New Hope, The Empire Strikes Back, Return of the Jedi, with no digital enhancements — the complete series, at the time.

We sat like anthropologists, observing our perfect test subject, completely silent to avoid spoiling anything, watching him discover this strange new world. “Wait, this is the beginning?” he asked as the intro scrolled across the screen “Why does it say Episode IV?” And then: “Whoa, they just blew up the whole planet?” And: “He can strangle people with his mind?” And: “Oh my god, they’re freezing Han?”

By the time we got to the most famous line, the line, the spoiler it’s virtually impossible not to hear at some point growing up — “Luke, I am your father” — the look on my friend’s face was one of pure wonder. I could not remember a time when I didn’t know who Luke’s father was, and I envied the excitement he was feeling, the unadulterated thrill of discovering something that, though verging on the cliché for me, was completely fresh territory for him. I kept thinking, How lucky he is to get to see this for the first time now.

As adults, it’s easy for us to feel that everything fun is already finished, that all the worlds have already been thoroughly mapped, especially when it comes to books. The last time I felt that childlike glee of discovering a new world was with Harry Potter, and by that time I was already in college. Now Harry has vanquished Voldemort. Aslan has fought Last Battle. Frodo has destroyed the One Ring. Katniss has — well, in case you’re waiting for the movies, I won’t spoil it for you.

But really, you don’t have to be young to experience that excitement. Here are five children’s series you might have missed when you were younger (and please add your favorites in the comments, too). Each offers a thoroughly imagined world that’s immersive enough to make you feel like a kid again, with writing sharp and smart enough to satisfy a book-loving adult. If they’re unfamiliar, I envy you: how lucky you are to get to read them for the first time now.

1. The Wolves Chronicles by Joan Aiken (12 books starting with 1962’s The Wolves of Willoughby Chase)

Aiken’s series is set in an alternate version of 19th century England, in which James II was never deposed and the Hanoverians — that would be the ancestors of today’s royal family — scheme against the rightful ruler, James III. Stay with me.You don’t need to know or even like history to enjoy this series, which centers around a plucky, streetwise Cockney girl named Dido and her younger sister, Is, and includes a healthy dash of fantasy while still being grittily real.

Wolves roam London at night. There are hot-air-balloon chases, plots hatched on Nantucket whaling ships, and hypnotic puppet shows. In The Stolen Lake, Dido journeys to a strange country ruled by Queen Ginevra — better known as Guinevere — who has been awaiting the return of her husband, King Arthur, for hundreds of years. In Is Underground, Is ventures into the terrifying mines — worked by kidnapped children — to rescue her missing cousin. Aiken’s series is hardly known in the U.S., and I don’t know why: she’s the forebear of steampunk and all kinds of other historical-fantastical mashups.

Oh, and did I mention that Edward Gorey did the book covers? Yeah.

2. Howl’s Moving Castle and Castle in the Air by Diana Wynne Jones

Can two books count as a series? I vote yes, because these are too good to leave off the list. Howl’s Moving Castle was made into an animated film by Hayao Miyazaki in 2004, but even the master couldn’t capture all the incredible flourishes of the book. Sophie, the eldest of three daughters and certain she’s therefore doomed to be a failure, is transformed by an angry witch into an old woman. Forced to flee her home, she talks her way into in the moving castle of the title: inhabited by Howl, a youngish, temperamental, and very vain wizard; his apprentice Michael; and a curious and powerful fire demon named Calcifer. Sophie and Calcifer strike a bargain: he’ll take the spell off her if she can break a mysterious bargain he’s made with Howl — but what is the bargain, and what will it cost to break it?

The novel is slyly funny, with gentle sendups of both fairy-tale tropes and modern-day life — at one point, Sophie and crew end up in a small town in Wales. (Don’t ask; just get the book, trust me.) Lit-nerds will delight in the John Donne poem that plays a central role in the plot. It’s clever and deeply satisfying, as is its sequel, Castle in the Air, which gives the same treatment to Arabian Nights territory.

3. The Stanley Family series (The Headless Cupid, The Great Stanley Kidnapping Case, Blair’s Nightmare, and Janie’s Private Eyes) by Zilpha Keatley Snyder

Zilpha Keatley Snyder is surprisingly unknown, given how prolific she is: she’s written more than forty books (three of them Newbery Honor books) and is still going. As a kid, I read all of them I could find, but my favorites are — and still were — the four books about the kids in the Stanley family: sensible David, precocious Janie, stolid Esther and her eccentric, prescient twin Blair, and cranky, adolescent stepsister Amanda, whose arrival shakes up the family.

In the first book, The Headless Cupid, Amanda arrives at the Stanley house, bored, bitter at her mother for remarrying, and — wait for it — obsessed with the occult. Her prosaic new stepsiblings decide they want to learn about the dark arts as well, but things start to get a little creepy when they learn about the poltergeist that once haunted their house. Snyder’s vivid characters keep the series firmly grounded in reality, though, and the series could be a master class for writers in any genre: create interesting and dynamic people, put them together, and let the sparks fly. In the following books, there’s a kidnapping in rural Italy, a (possible) monster roaming the neighborhood, and a mysterious rash of dognappings, but at heart the focus is always on the dynamics of this quirky family.

4. The Half Magic Series (Half Magic, Knight’s Castle, Magic by the Lake, and The Time Garden) by Edward Eager

The three series I’ve mentioned above could be considered YA from a time before “YA” was a thing, but the Half Magic series by Edward Eager are clearly meant for children Despite the younger audience, though, adults — especially book-loving adults — will still adore these stories of unabashed magic.

Each takes a traditional chestnut of children’s lit — the magic talisman, a wish-granting animal, time travel — and gives it a fresh twist. For instance, in Half Magic, four brothers and sisters find a magic charm that grants them exactly half of what they ask for, and in Knight’s Castle, a boy discovers that his toy castle comes to life at night. Jo and the Little Women, Merlin, Ivanhoe, and many more literary figures have cameos, making these books parents and kids will enjoy on different levels. Each book stands alone, but figuring out how the stories are connected — and then watching them overlap—is part of the fun.

5. The Vesper Holly series by Lloyd Alexander (Six books starting with 1987’s The Illyrian Adventure)

Many people know Alexander’s Chronicles of Prydain, including The Black Cauldron (and if you don’t, get thee to a bookstore or library). But fewer people are familiar with his marvelous heroine Vesper Holly and her adventures. Vesper is a teenage orphan, ferociously intelligent, insatiably curious, and completely unfazable; picture a teenage, female, red-headed Indiana Jones. She drags her elderly and devoted guardian, Brinnie, across the globe to just-barely-made-up lands — Illyria, torn by centuries-old civil war; El Dorado, where Indian tribes grapple with encroaching industrialization; Jedera, a desert land with an immense, ancient library under siege. In her first adventure, she makes an archnemesis, Dr. Helvitius; in each book, she thwarts another of his plots. These are fun, smart books, with witty characterization and sparkling writing. Growing up, I wanted to be Vesper, and now that I’m grown up, I still kind of do.