Damon Lindelof’s moody psychological thriller/apocalyptic drama The Leftovers is nearing its end—the season finale airs on HBO this Sunday—and I’m just as intrigued about what music they’ll be using as I am about what will happen in it.

The show’s elegant, evocative classical music score is by German-born UK-based composer Max Richter, the main Leftovers theme a powerful piece of urgently ascending strings that were used in the first season’s opening credits, while a more condensed chamber version pops up in appropriate moments throughout the next few seasons. Richter’s other classical works seem to carry just as much weight and tend to elicit heavy feelings ranging from deep dread to hopelessness, but his fine emotive hand is most notable in the dour, soul-crushing melancholy of the “Departure” piano theme; it plays in general reference to the tragedy that is the premise of the show—the disappearance of 2 percent of the world’s population (they’re called the Departed and the event is referred to as the Departure)—and also seems to pipe in when anything truly significant is happening.

But the show wouldn’t work so well on an emotional level without a soundtrack that deftly taps (mostly) modern music to carry the mood and narratives along for each episode. Not to mention Season 3’s mode of switching up the tunes that run with the opening credits to set the tone and foreshadow what’s about to happen. Like the Perfect Strangers theme in the second episode, “Nothing's Gonna Stop Me Now," where Nora goes to meet Mark Linn-Baker, the only remaining cast member of that ‘80s-era show who didn’t Depart, who lures her in because he's found a way to potentially join the Departed. (She lost her entire family and spends much of the show coming to grips with it, or pretending she's fine when really she's so, so not.) Or Richard Cheese’s jaunty version of Depeche Mode’s “Personal Jesus” opening “Crazy Whitefella Thinking,” which follows Kevin’s dad on his journey to stop the end of the world singlehandedly (or so he thinks), while also subtly referencing his Jesus figure son, the walking miracle who came back from death multiple times. The slinky sad "This Love is Over" by Ray LaMontagne and the Pariah Dogs opens in “G’Day Melbourne,” the episode that culminates in the break-up of Kevin and Nora—and the same episode that delivers three different versions of A-Ha’s “Take On Me,” in very different settings, to convey very different moods, the original playing as Kevin drives off with his dad and leaves Nora alone in their hotel room getting soaked by the fire alarm sprinkler. They’re both broken but can’t seem to reach each other, nor can she reach the “other side,” or where she imagines her broken children have gone.

“Certified” taps the Gravediggaz’s “1-800 Suicide.” while in the series of scenes that follow the opening credits and show Laurie’s suicide attempt before she joins the Guilty Remnant cult, a chamber orchestra version of Metallica’s “Enter Sandman” adds a nice bit of drama, its very lack of lyrics and use of double bass making it so much more compelling that the original. (The first season also tapped a classical version of a Metallica song, “Nothing Else Matters,” for its last episode—the one where the Guilty Remnant’s nefarious and ugly plan comes to a head and the town reaches a riotous boiling point.)

A grave piano version of the Pixies’ “Where Is My Mind” pops up sporadically throughout the second season as Kevin starts realizing he’s definitely not a well person despite leaving the town that made him crazy, and it comes to an epic head in episode 7, “A Most Powerful Adversary,” because Kevin is quite literally losing his mind and only discovers his mental health is truly fucked when he “wakes up” and finds that his other self (the one that does things he doesn’t remember when he’s normal) has kidnapped the leader of the Guilty Remnant.

Whenever Kevin wakes up on the other side (is it heaven or purgatory or… something else entirely?), you get the grandiose drama of Nabucco’s Chorus of the Hebrew Slaves (Va', Pensiero, Sull'ali Dorate), its chorus's theme of exiles singing about their homeland working on a few levels; and when he’s forced to do karaoke of Simon and Garfunkel’s “Home” to get himself back home from the other side, it’s an obvious choice but comes off as utterly poignant and heartbreaking with his trembling, off-key, is-this-really-going-to-work? delivery.

When Kevin has to cut the key from the chest of his “twin,” to carry on with the end of the world (or, the end of the other side), we get the Beach Boys’ “God Only Knows,” because essentially, he’s cutting out his own heart as he realizes how broken he truly is and that his priorities are totally fucked and he walked out on Nora when she needed him most—and the end of the world is probably dead ahead, so he might never get a chance to redeem himself. That penultimate episode also closes with Patty Duke's version of Skeeter Davis’ nostalgia-milking, heavily disconsolate (and in some ways direly prophetic) ode, “The End of the World,” which drives the heartbreak home ever deeper.

I could go on and on, break down each episode song by song, but it’d be better not to give away too much more, if anyone reading this ultimately decides to stream through all three seasons. Because it’s a pretty epic show and it’s about to end and it’s worth binging, even if it hurts your heart sometimes while doing it, because it can be really heavy and strange, often both at once. But it’s worth it, if only so you can consistently admire the steaming hot hunk of beauty that is Justin Theroux.