The ’80s may be the key source of hallmarks and hits for "Stranger Things" to riff on (or rip off, depending on your opinion of the show), but like many sequels, for season two of Netflix’s insanely successful breakout hit, creators Matt and Ross Duffer found a new beloved text to crib notes from: itself.

There’s another new outer-dimensional menace hailing from the Upside Down with a toothy plant mouth ravaging the small town of Hawkins, Indiana, and taking poor little Will away from his friends and loved ones. There’s another new girl outsider to replace Eleven in our lead gaggle of nerds, as well as another new bully now that fluffy-haired Steve’s a reformed good guy and another new food-loving stranger with a signature snack to the group.

There’s even yet another puzzle from Will strewn across the Byers household, this time a sprawling map of crayon drawings instead of a Christmas light Morse code. For much of "Stranger Things," the show is obsessed with reliving the past – not just the ’80s but its own past.  

And that’s not such a bad thing. As the first season showed, the Duffer Brothers are pretty good at turning their familiar references and inspirations into something fresh and fun – and season two mostly pulls off the same trick, taking the old and making it new again. Or at least new enough.

It’s Halloween, one year after the events of "Stranger Things" season one, and everyone’s attempting to come back down to earth from Will’s abduction into another dimension. The boys are just boys again, moving on from their life-or-death adventure by playing the life-or-death adventures of "Dragon’s Lair 3D" at the local arcade.

Nancy and Steve are prepping for college and falling in and out of love as high school lovebirds do, while Joyce Byers (Winona Ryder) has even moved on to find herself a new love in big-brained Radio Shack manager Bob Newby (new addition Sean Astin, obviously). Meanwhile, Sheriff Hopper (David Harbour) is back to investigating seemingly mundane Midwestern mishaps, like pumpkin patch rivalries.

Something dark, however, is still lingering over Hawkins and poor little Will, who randomly finds himself mentally jettisoned to the Upside Down where a gigantic smoke Cthulu looms over the city. What’s it mean? Does it have to do with the completely restaffed but still ominously secretive Hawkins Labs? And what’s that rumbling noise coming from Dustin’s garbage can? I’ll save the show’s surprises for you to discover, but it should come as no spoiler that they come wrapped in ’80s needledrops and nostalgic cinema callbacks.

For some, all of those allusions make "Stranger Things" merely a poppy pastiche, taking place in the Buzzfeed quiz version of the ‘80s rather than the actual ’80s. But credit where credit is due: The Duffer Brothers go all out when it comes to the period detail, complete with the old school packaging and retro fashion choices.

It’s a fun little trip into the time machine – complete with references big and small to the movies that clearly inspired its creators.

The red storming sky of Will’s Upside Down nightmares, for instance, recalls "Close Encounters," while a late climactic scene is just some spilled split pea soup away from being literally "The Exorcist." "Aliens," however, casts the largest shadow over season two, from a bug hunt sequence to the casting of Weyland-Yutani lackie Paul Reiser as the new head of Hawkins Labs.

Beyond the clever reworkings and slight tweaks to make these callbacks fresh, the real secret to "Stranger Things" avoiding merely becoming a congratulatory game of Spot The Reference is how much the show cares about its characters. The plot may work with familiar elements, but the kids feel like their own special creations, especially in season two where the aftermath of the previous season, and its current effects on those left behind, is allowed to marinate (or fester).

That care extends to the performances. The boys are all still a delight to hang with; even if Mike (Finn Wolfhard) feels a little underwritten this year – maybe filming "It" was keeping him busy? – Dustin (Gaten Matarazzo) gets a bigger spotlight partnered up with Steve, an odd couple pairing that ends up perfectly funny and sweet. Noah Schnapp’s Will also gets upgraded from plot device to … well, another plot device, but at least he actually gets to hang around this time.

Plus, his performance is genuinely great, playing the most devastatingly tortured member of the gang, haunted by his past trauma – and clearly something else. An early scene of him attempting to stand up to his demons is one of the series’ most frightening moments so far, thanks to his heartbreakingly vulnerable attempt at strength.

Even the newcomers get to make their mark. It’s a credit to Astin that his character’s predictable emotional beats hit as much as they do, while Reiser is consistently fun cleverly reverting and inverting of your expectations of the former corporate stooge. And while it’s one of the show’s lesser storylines, Brett Gelman’s weaselly private eye is a hoot, bringing a peculiar oddball comic energy to all of his scenes.

Alongside the kids, the grounding star of "Stranger Things" is Harbour’s Hopper, who’s also given even more to do and is more than up to the task. His performance is so gruffly charismatic and entertaining, but his storyline with Eleven especially works because of the weight of his child’s death – mostly unspoken but deeply felt thanks to his acting.

Oh, by the way, Eleven’s back – but don’t celebrate too hard, because unfortunately this is one of the season’s lesser choices.

For most of the sequel, Millie Bobby Brown’s breakout character is kept separated from the boys and from the main storyline, locked away in a cabin for her overprotection by Hopper – a bummer not only because she crackled so well with the boys last season but also because her storyline then always feels besides the point. There’s some decent character stuff going on there, involving Eleven hunting down her mom, but it just feels shoehorned into the show, a feeling that only gets worse when she gets an odd, unnecessary solo episode with some goofy "Terminator"-inspired street punks right when the main plot is finally starting to boil.

It could be a palate cleanser; instead, it plays like a distraction with too much time spent on too little meaning other than keeping the good guys' telekinetic trump card on the bench for now. By the time "Stranger Things" does finally get everyone together, there’s barely an hour left in the show – and even most of that is spent split apart too.

The story doesn’t need any extra help in stalling either, as the early episodes take a good while to really start coming together. Some of that’s good, as it dives into the characters’ post-trauma psyches; some of it … not so much. The audience ends up spending a lot of time needlessly #JusticeForBarb-ing, dealing with Dustin’s drama with a special pet that ends predictably, and establishing the new girl Max (a solid Sadie Sink) and her bully of a brother who ends up being a lot of energy wasted on not much payoff (he sure looks the part perfectly, though).

The first three episodes take a frustrating amount of time to cohere into its main mystery – something that gets even more unnerving when the finale occasionally feels like it’s rushing through character and plot beats.

But that finale – and the big, creepy PG-rated freakout material leading up to it – is all breathless blockbuster entertainment made exceptionally well. The Duffer Brothers – along with their fellow directors, including former Pixar great and "John Carter" scapegoat Andrew Stanton – know how to concoct a creepy, intense moment or break that tension with a perfectly placed wisecrack or charming glimpse into adolescence. They’re very effective old school sci-fi thriller craftsmen – and thanks to the heart they put into their characters, the thrills and stakes consistently land more than just a cute collection of homage.

"Stranger Things" isn’t going to sneak up on anybody anymore. It’s no longer just a fun summer streaming surprise, and it’s not the antidote from the modern blockbuster the first season supposedly was. It is that blockbuster now. But with "Stranger Things" season two, it’s made the transition impressively well, going bigger without blowing itself up and continuing to make something fresh out of familiar pieces, something new that feels just like how you remember it.