Aaron Moorhead and Justin Benson continue their hot streak of inventive, idiosyncratic science fiction with a refreshingly heartfelt time-travel thriller.

Aaron Moorhead and Justin Benson are doing some of the most interesting, inventive work in the mid-budget sci-fi/horror space right now, and it’s impressive just how consistent their output has been. In a world of disposable science fiction thrillers and hokey premises with shaggy effects, Moorhead and Benson (who both come from visual effects backgrounds) have long since honed the ability to leverage economical effects into thematically-rich stories. Resolution, Spring, and The Endless are show-stopping examples of their idiosyncratic appeal. Their latest, Synchronic, has bigger names and a slightly bigger budget, but these leaps towards mainstream filmmaking conditions haven’t softened their edge one bit.

Where their previous works operate in a loosely-connected universe of eldritch horror, here Synchronic turns its eye to time-travel, represented by the designer drug of the film’s title — a pill that will make you experience fluctuations in time. It’s trippy, but also dangerous, as evidenced by the increasingly bizarre death scenes that New Orleans paramedics — and longtime best friends — Steve (Anthony Mackie) and Dennis (Jamie Dornan) run into. They find bodies burned to a crisp with the rest of their environment pristine, or people dead of a snakebite when there are none in the area.

It’s a disquieting part of their job, one which only puts more strain on their dynamic; Dennis is the settled family man, with a wife (Katie Aselton) and daughter Briana (Ally Ioannides), while Steve’s still living a life of empty alcoholic debauchery, with only his adorable pup Hawking to keep him company. But Steve soon learns it’s not the drugs or the job that’ll kill him — it’s a tumor on his pineal gland that’s given him only weeks to live. Not long after that, Briana goes missing, and Steve suspects Synchronic (which can make users with un-calcified pineal glands, like teenagers or, say, paramadics with unique pineal tumors, actually travel back in time) is to blame.

Both out of a sense of moral good, and an obligation to his best friend, Steve buys up all the Synchronic left in the area and starts to experiment, searching for Briana through time. It’s here that Benson and Moorhead begin to really have fun: the film’s first half is effectively atmospheric, filming New Orleans with suitably street-lit atmosphere and building a couple of relatable leads in Mackie and Dornan’s characters. But once Steve starts his quest, filming himself taking the drug and tracking the results, Synchronic builds a scintillating world filled with snapshots of a dangerous past.

The best time-travel stories — Back to the Future, Looper — recognize that they only have to obey the rules they set up for themselves, and Synchronic sets up some nifty constraints that make for natural sources of tension. You can’t really control how far you travel back, save for specific locations tying you back to specific time periods. You have to be in that exact spot, too, in order to travel back. Benson and Moorhead make great use of these limitations to craft some impeccably-staged trips to the past, from the Ice Age to Spanish colonialism to the Jim Crow era — which also serve as stark reminders of the violent, racist history of America.

But Synchronic‘s greatest trick is the way it crystallizes its neat, slickly-presented time-travel shenanigans into a bittersweet story about friendship and the impermanence of life. Steve’s always lived in the present, never thinking about anything more than his next drink; now, with a deadly illness forcing him to reckon with his life choices, he sees one last chance to make good for the few people who’ve been there for him. It’s a journey filled with grief and self-reflection, using time travel as a nifty metaphor for the ways we try to run from our ugly pasts, and the things we leave behind in the process.

It’s that emotional core that elevates Synchronic above the already-impressive elements of its inventive, economical effects and the twisty premise.

Mackie acquits himself well, too, bringing his natural blend of Denzel-like charisma and steely-eyed intensity to the role. Dornan, for his part, has admirable chemistry with his co-lead, the two feeling like old friends who’ve been with each other through thick and thin, even as their lives have grown apart. If you’ve ever been on either side of a friendship where one person feels more put together than the other, and the sense of obligation that engenders, Synchronic will tear your heart out.

It’s that emotional core that elevates Synchronic above the already-impressive elements of its inventive, economical effects and the twisty premise. It’s one thing to come up with a mysterious designer drug that makes the world around you literally melt away into the past; it’s quite another to turn that journey into one man’s desire to fix his mistakes, and save the people he loves, before he’s gone.

Benson and Moorhead have always been able to affix their high-concept stories with smarter, more intimate stories of love and male friendships, and the way time makes martyrs of us all. Their latest, I’m pleased to say, is yet another brick in a mighty edifice of work that I can’t wait to see built up even further.

Synchronic is currently playing in select theaters and drive-ins.

Synchronic Trailer: