'Two Vines' is due out Oct. 28

Australian psych-pop weirdos Empire of the Sun had a spiritual awakening before they began writing for their third record. “Buddha was revealed to me,” says multi-instrumentalist Nicholas Littlemore. “And the theme really rushed through me: I wanted to write about plants and love and the planet.”

To achieve this vision, Littlemore and bandmate Luke Steele recruited Fleetwood Mac frontman Lindsey Buckingham, Prince’s onetime protegée Wendy Melvoin, and David Bowie collaborators Henry Hey and Tim Lefebvre for a result that’s more akin to the interstellar psychedelia of their 2008 debut than 2013’s more Top 40-radio-baiting Ice on the Dune.

Here, Littlemore and Steele take EW behind their trippy vision.

ENTERTAINMENT WEEKLY: When you began work on this album, did the two of you set any goals for the music?

STEELE: The beginning and end of everything is that we’re always trying to write great songs. It’s the patchwork of the Empire. At this point in our lives, we wanted to make a record that’s more bare and honest. We want to get to that point where you put the record on and feel like we’re talking to you.

Ice On The Dune was set in the 31st century. Does Two Vines have an equally defined setting?

LITTLEMORE: I had a profound experience about a year and a half ago. Buddha was revealed to through meditation and that really affected me. The theme really rushed through me: I wanted to write about plants and love and the planet. We had the idea of an image where the future of the world would be New York City, or any of these great cities, but completely covered in vines.

What was it like working with Lindsey Buckingham?

STEELE: I have these music nights with my wife where we sit back and listen to old records, and I always email my manager saying, “Can you get in touch with this guy, that guy,” my heroes. So we reached out to Lindsey and it just so happened he’d just got off the road with Fleetwood Mac and was in L.A. He said he loved the band and would love to come to the studio.

LITTLEMORE: Fleetwood Mac had been a very strong influence on our lives, but you know, sometimes you meet these heroes of your and then they let you down. But he fell right in — he felt like a member of the band.

I understand you have a unique producing-style.

LITTLEMORE: It’s sort of similar to when you were at school trying to make a document look old so you burn the edges. We run the music through all this old gear. Sometimes we say, “Oh, I don’t even know if the audience notices.” But even if they don’t notice sonically, maybe they feel something different — maybe it touches them in a nostalgic way.

STEELE: It has so much more of a soul, a bit more nourishment, than modern gear. It’s like how I only buy old guitars now. When you play an old guitar, it has so many unfinished songs to get out of it.

Have you considered how you will present the album? Staging and costume-design have always been so huge for the band.

LITTLEMORE: It’s a lot more minimal. After my experience, I’m wearing the Buddhist color, the orange, and little else. I didn’t want to wear beads or any adornment. Luke is very very basic blue silk. He still has a headpiece but we’re trying to pull it back toward the essential.

STEELE: It’s like you’re walking into the jungle and you have one garment that you put on. We’re going to simplify the process — but having said that we’ll probably end up with pyrotechnics and animals on stage.

After the 2013 album, there were rumors of a rift between the two of you. How are you now?

LITTLEMORE: There always is with creative partnerships, especially with two individuals as intense as us, but there is a greater good here. The music has always risen higher than our egos, which is amazing, because our egos are really high.

STEELE: It’s a really strange relationship, but when it works, there’s nothing like it in the world.

“Walking On A Dream” cracked into the Billboard Hot 100 this year, eight years after it originally released. How does that feel?

LITTLEMORE: Where my grandmother lived in Sydney, you could walk down a hill to the harbor. I did this one day and found a bottle, and there wasn’t a message in it, but there was a fish in it. I let the fish go but thought, in my imagination, that the fish had been living in the bottle for years. Maybe a song is something you send out and it comes back with another story added to it, and then another one, another one, and another one. Everything you ever do, it’s going to come back in some way.

For exclusive details on the biggest albums coming this fall, pick up the new issue of Entertainment Weekly, on newsstands Friday, and see all of our Fall Music Preview coverage on EW.com.