You know that clicking sound that the back of your throat makes when it’s really tired? That deep door-creaking thing? The one that disappears completely when you speak at any volume above a mutter? That clicking sound is where Chicago rap teenager Lucki Eck$ lives. That clicking sound almost never shows up on rap records, and that’s because rappers almost never speak quietly enough for that clicking sound to manifest itself. Even relatively quiet, inwardly focused rappers are working in a form built on declarative toughness, on laying out clearly why you’re better than anyone else around you. It’s an extroverted, competitive form of art, and it’s not really meant for people who are living inside their own heads. But Lucki Eck$ is an exception: A rapper who always sounds like he just rolled out of an unmade bed, whose brain seems permanently awash in chemicals, who’s persistently more interested in figuring out the workings of his own head than in talking shit about anyone else. On “4th Commandment Broken,” the first track from his new Body High mixtape, there’s a moment where Eck$ stops rapping entirely and, through a stoned haze, attempts to remember the plot of the brand-new movie Lucy, seemingly just from its trailer: “They like, ‘What’s gonna happen when she use 100% of her brain?'” It’s the type of stoner-logic musing that makes Body High maybe the most purely interior mixtape I’ve heard this year.

“4th Commandment Broken” isn’t a reference to anything Moses brought down from Mount Sinai. Instead, it’s about the Biggie Smalls song “10 Crack Commandments,” and, in particular, #4: “Never get high on your own supply.” Eck$ raps from the perspective of a Xanax dealer who can’t stop popping the pills he’s supposed to be selling: “I’m going crazy / I’m losing money off this shit / It got me lazy / I don’t even wanna serve no bars / Hire a new waiter.” That’s a crucial wrinkle to what Lucki Eck$ brings: He’s making music as someone pickling his brain fluid in the drugs he knows he shouldn’t be taking, that he knows will drain his money away while they kill him. So much rap is about immediacy and mastery that it’s weirdly refreshing to hear someone making this kind of expansive psychedelic rap music, and making it about weakness, about his own personal failings.

Musically, Body High recalls the hazier, more tripped-out edges of late-’90s and early-’00s abstract dance music. These instrumental tracks (some of which come from SKYWLKR, Danny Brown’s tour DJ and frequent production collaborator) would’ve been right at home on, like, the Macro Dub Foundation compilation. The synths feel like they’re coming from somewhere deep underwater. The drums hit like wet pillows. The bass isn’t a rumble or a foghorn; it’s a soft, soothing thrum. And the IDM connection becomes concrete late on the tape, when Eck$ raps over a slightly filtered version of Björk’s Matmos-produced Vespertine classic “A Hidden Place,” something I can’t believe I haven’t heard a rapper try before. Eck$ worked that same aesthetic on his debut tape, last year’s Alternative Trap, but he’s drifting even further into it on Body High — leaving any glimmers of traditional rap toughness behind on the shore, watching them get smaller and smaller. Body High pairs nicely with FKA twigs’ similarly folded-in-on-itself LP1, something made obvious when you remember that twigs directed the “Ouch Ouch” video for Eck$. It’s not as fleshed-out or desperate as twigs’ album, but it’s made from that same higher-than-a-motherfucker perspective.

There’s only one guest rapper on Body High: The unknown-to-me Ran$ah, who adds a slight energy-boost to “Can’t Blame You.” I’m not sure, but Eck$’s best recent track, the Danny Brown collab “Weightin’ On,” isn’t on Body High. As strong as Body High is, and as completely as it taps into Eck$’s staring-at-a-black-light-poster aesthetic, it gets a bit numbing by the time its 12 tracks are over. So “Weightin’ On” is an encouraging sign, an indicator that Eck$ is capable of switching his style up to the point where it makes sense to hear him on the same track as a human energy-bomb like Brown. Eck$ still has places to go, but Body High works as proof that he’s tapped deep into a feeling that rap, whether in its many mainstream or underground forms, rarely acknowledges: The idea that getting lost in yourself can be a scary and pleasurable experience.

Download Body High here.