With Part 1 of Stranger Things' latest season dropping this May, fans may be scrambling to refresh their memories on the past three seasons. Redditors have been buzzing about small details they've appreciated in Stranger Things that contribute to the show's deep sense of heart.

From sentimental details of Hopper's former family life carrying over to his new life as Eleven's guardian to subtle costume details that convey the characters' emotional state, the Duffer brothers and their team seem to rarely leave set pieces and props up to chance. Looking back at past details may prepare Stranger Things fans for season 4, as the characters' stories come full circle, or to the Upside Down and back again.

Hopper's Life Was More Complicated Than Viewers May Know

Jim Hooper with his hand holding his daughter's face with his wife beside him on Stranger Things

GodDammitGrigori pointed out part of Hopper's past that the series communicates between the lines. They wrote, "I honestly really like the casual and discreet references to Hop's service in Vietnam."

Related: The 10 Best Characters In Stranger Things

They also added evidence: " The box labeled "Vietnam" we see under his cabin when El looks around, his controlled use of the Colt 723 on semi-auto only, and, of course, the quite visible symptoms of poorly-treated PTSI we see throughout (although this also has a lot to do with his daughter's death)." Though Hopper has certainly gone through more trauma since he met up with Joyce and the kids, hopefully having a solid support system again has finally led to some healing.

Hopper Kept His Daughter's Old Books

A split screen of Jim Hopper reading to his daughter and hugging Eleven in Stranger Things

Heartwarming moments in Stranger Things win fans over and keep them coming back season after season, and it's the same way for Reddit user cariett222. They wrote, "I loved the way that Hopper read from the same book to his daughter and to Eleven. You see it when he's sitting with Sarah reading to her in hospital and then in season 2 he sits on Elevens bed with her and reads it."

Redditors agreed that the book appeared to be Anne of Green Gables and that sharing the story with Eleven was an important step in letting her into his heart.

The Answer To How Hopper Survived

Jim Hopper in his police officer uniform in Season 3 of Stranger Things

When Hopper disappeared off a treacherous platform at the end of season 3, fans weren't sure if he survived the fall. However, hints to a Russian prison and trailers for season 4 confirmed that Hopper miraculously survived.

Reddit user tarannn25 offered a handy explanation for it; "the last episode of season 3 clearly shows a ladder to climb down the platform,. and that's how i think hopper escaped successfully from there." However he did it, fans are thrilled Hopper will be sticking around.

There Were Hints In The Numbers

Mike Wheeler speaking into his walkie talkie on Stranger Things

With characters named after numbers, the series isn't shy when it comes to mathematical Easter eggs. When they are separated, Mike and Eleven each count the days since they've seen each other.

Redditors realized there was a special link to the number of their separation day count; "The number of days (353) add up to '11,'" 65fairmont wrote, and added, "Hopper and El use radio channel 11 to speak to one another. Mike also uses channel 11 on his walkie to call El every night during season 2." These hidden patterns are just a few more sweet gestures in Mike and Eleven's adorable tween romance.

Bob Dropped Plenty Of Film References

split screen of Sean Astin on Stranger Things dressed as Dracula with vampire teeth and as a teen in Goonies

Stranger Things was blessed by Sean Astin as Bob Newby for only a short while, but the Goonies star became a vehicle for the writers' sneaky film references. Besides his expert Dracula costume, one deleted Reddit user posted about a moment with a potential double-meaning; "when bob says take a step into the future and joyce says future can wait ironically bob is using same camera as marty in back to the future." Though Back to the Future came out in 1985 and Season 2 of Stranger Things is set in 1984, the writers might have wanted to pay tribute to another creative inspiration to come out of the '80s.

Related: 10 Fan-Favorite Stranger Things Characters, According To Reddit

The Redditor pointed out another possible film connection; "Bob's fear of clowns and conversation about the balloon is very IT-related. Timelines sync up." Though, if Bob died in 1984, he wouldn't know about Stephen King's 1986 thriller or the 1990 TV series. Whether or not these references were intentional, the fans always got a kick out of Bob.

They Replayed A Sentimental Song

Will and Jonathan Byers listening to a record with their backs to the camera on Stranger Things

Stranger Things has always used music as a key factor in progressing its narratives. Who could forget "Should I Stay Or Should I Go?" by The Clash being used to communicate with a possessed Will Byers? Redditor Itsyaboiblue picked up on a subtler musical motif that had them looking more deeply into scenes: "the callback in the finale of s3 to the 4th episode of s1 with the “We Can Be Heroes” song. Both times it’s played are super emotional."

Another Reddit user arczclan responded with additional details; "The first one is played when Will’s “body” is found ... The second one when Hopper’s letter is read." The version played is a slowed-down cover of David Bowie's "Heroes" performed by Peter Gabriel, with swelling strings and soulful vocals that add new resonance to already the wistful lyrics.

There Are Subtle Costume Details

Mike, Dustin, Caleb, and Will wearing Ghostbusters Halloween costumes trick or treating on Stranger Things

Redditor k_is_for_kwality pointed out a detail other viewers might not have noticed in the Halloween episode. They wrote, "Will’s costume is slightly different than the other three, because the other more affluent families just bought a costume while Joyce decided to make Will’s herself to save money."

madmaxx_84 remembered Joyce sewing the costume in an earlier episode, and the earlier writer appreciated the representation of a less well-off family getting creative on the pricey holiday. Stranger Things may deal with otherworldly problems every episode, but it also makes a commentary on social issues the characters face as well.

Characters' Clothes Also Hinted At Growing Up (Or Not)

Split screen Will Byers wearing the purple dungeon master cloak and a collared shirt on Stranger Things

Season 3 saw the Stranger Things kids grow up in a big way, with new relationships forming, growth spurts, and new interests. However, as Pizzagay121 wrote, "Will looked so out of place compared to the rest of his friends ... it makes sense because he wants to be a child still and play D&D all day but because he spent most of his childhood in season 2 in a hospital he never got a chance."

Related: Windbreaker To Romper - Eleven's Clothing Evolution On Stranger Things

They also pointed out that he seemed to be wearing the same clothes as he did in season 2, which were too small for him. This seemed to represent his stalled development from his traumatic experiences in the Upside Down.

Mike and Eleven's Bedrooms Shared This Detail

Mike Wheeler lying on Eleven's bed with a bird poster above his head with Eleven sitting behind him on Stranger Things

Mike and Eleven's romance grew out of their sturdy friendship, and their connection is evident even in their bedroom sets. Redditor ArmsInTheRain shared, "Something I was so smug about noticing was that when El is living with Hopper in season 3, she has a poster of a bird by her bed - the same poster is hanging in Mike's basement in season 1!" Another Reddit user, BSJ-Pavee, pointed out, "if you look with attention, you can see a lot of stuff that was in mike basement."

This sweet gift makes total sense since Eleven's first bedroom was Mike's basement, and her boyfriend must have known she needed a piece of him to feel settled at Hopper's. Even though Mike and Eleven are on opposite sides of the country by the end of season 3, fans expect Stranger Things season 4 to have quality content for these star-crossed young loves.

An Earlier Season Hinted At Season 2's Poster

split screen of the Stranger Things 2 poster and The Dark Crystal poster seen in Will's bedroom in Stranger Things Season 1

With Stranger Things' intentional horror references and refined aesthetic, it's no surprise that the Season 2 teaser referenced a scary movie with a stunning poster. A deleted Redditor clued others into the origin of this reference, and it's cleverly buried in season 1. They wrote, "In the very first episode of the show, there’s a poster in Mike’s room, of a movie called The Dark Crystal ... it caught my eye, because it bears an uncanny resemblance to a promo poster for Stranger Things 2."

The film in question is a fantasy-esque feature that came out in 1982. Beyond it being relevant pop culture knowledge for the show set in the same decade, Netflix could have also been subtly promoting the prequel series they released in 2019, The Dark Crystal: Age of Resistance.

Next: 10 Major Flaws Of Stranger Things That Fans Choose To Ignore