Stranger Things has made its mark on pop culture, and it's continued its signature style of 80s pastiche storytelling with the release of the second volume of season four. Interestingly, the sci-fi horror series expanded the characters based on the actors' interpretations. When they were casting characters, The Duffer Brothers only had a pilot script to work from.

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With so much influence from the actors, it should come as no surprise that these actors shaped scenes, even improvising moments that now define the hit Netflix series. During these improvised moments, the cast of Stranger Things was truly able to shine. These improvisations allow the cast to demonstrate their masterful grasp of their characters and define them in unexpected ways.

8 The Iconic Eggos Scene Was Made Even Better By Millie Bobby Brown's Improv

Eleven stealing boxes of Eggos

When considering a scene from Stranger Things that best embodies the show as a whole, it is impossible to overlook the moment when Eleven steals as many boxes of Eggos as she can carry from a local grocery store in season 1. Nowadays, fans can't imagine the scene unfolding any other way.

Millie Bobby Brown's Eleven was only supposed to grab one or two boxes before quickly leaving the store. As well as adding some comedy into the scene, Brown's decision to slightly augment the script made what could have been a much smaller scene incredibly memorable.

7 Parts Of The Breakfast Scene From Season 2 Were Ad-Libbed

The infamous breakfast scene from Season 2 of Stranger Things

While most of the infamously awkward breakfast scene was scripted, one of its most effective lines was the result of a small mistake during filming. This scene followed Nancy and Jonathan's first night together, which was ironically brought about by Murray teasing the two for their unspoken yet requited feelings for one another. It was crucial for Murray to be the all-knowing, comedic anchor within the scene.

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Funnily enough, the line that best hammered this point home was improvised after Brett Gelman, who plays Murray, accidentally dropped his forkful of scrambled eggs. Instead of falling out of character, Gelman was sure to capitalize on this moment and finishes the scene by flirtatiously uttering "oops." The spontaneity of this moment can be gleaned from Natalia Dyer's (who portrays Nancy) concerted efforts to remain in character after the fact.

6 Eleven's Exhaustion After Her Fight Scene With Billy Was All Real

Eleven collapses in Stranger Things

Although Millie Bobby Brown's immense talents never go unnoticed, many fans fail to realize how much of herself the young actor puts into her portrayal of Eleven. A prime example of this is when, after her intense fight with Billy in the locker room, an emotionally distraught Eleven collapses into Mike's arms.

Since this scene was draining for Millie Bobby Brown to film due to its intense emotion, her exhaustion was genuine. In fact, it is fleetingly evident that this moment caught Finn Wolfhard (who plays Mike) off guard. He briefly breaks character when he looks to the director for guidance on how to react to his co-star's physical and emotional fatigue.

5 Mike's Heart-To-Heart With Eleven In The Grocery Store Was Improvised

Mike and eleven in a grocery store

In season three, Mike pours his heart out to Eleven. Because of how effective and touching that moment is, many "Mileven" shippers would be surprised to know that it was improvised. Since Eleven dumped Mike earlier in the season, it was important that this scene showcased how much Mike cares about Eleven while displaying how hard it was for him to vocalize these feelings.

The spontaneity of Wolfhard's lines in this moment can be noticed when Brown tries her best not to laugh at them. Ultimately, her laughs were kept in the final cut because her reaction is true to her character.

4 "Don't Ya, Big Boy?" Was Ad-Libbed By Joseph Quinn

Robin watching as Eddie playfully flirts with Steve

One character who quickly charmed his way into viewers' hearts for his cool and caring demeanor was Eddie Munson, who is portrayed by Joseph Quinn. Although fans of Stranger Things are known to be skeptical of new additions to the already-established cast of characters, Eddie was a breath of fresh air for his playful interactions.

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One notable interaction that recently set the fandom ablaze was Eddie's playful flirtations with Steve in season 4 Vol. 2. Although this moment is very memorable and is becoming iconic in its own right, Eddie's line, "Harrington's got her ... Don't ya, big boy?" was improvised by Quinn on set.

3 Lucas' Call For Help In The Season 4 Finale Wasn't In The Script

Lucas from Season 4 of Stranger Things

Because Lucas was beginning to fade into the background for many Stranger Things fans, Caleb McLaughlin's stellar performance in season 4 was especially praised. With Lucas coming into his own throughout the season, one of his lines has stuck with fans since the season wrapped.

As Lucas can only helplessly watch as Max succumbs to Vecna's curse, he anxiously utters the line, "Erica, help." While reminding the viewer that Lucas and the rest of The Party are only children as they navigate these otherworldly events, this vulnerable moment grounds Lucas by putting into perspective how much he has to lose.

2 The Passionate Kiss Between Joyce And Hopper In The Russian Jail Was Unscripted

Joyce and Hopper sharing an intimate moment in Stranger Things Season 4

Ever since Joyce and Hopper started growing closer, fans have been waiting for them to share their feelings for one another. While this was only hinted at during season 3, the pair finally acted on their feelings when they were reunited in season 4.

Although their kiss near the beginning of Stranger Things 4's finale was scripted, Joyce and Hopper share an unscripted kiss that many fans agree is more powerful. Existing as another moment where the two can express their feelings, this improvised kiss serves as a testament to how intimately Winona Ryder (who plays Joyce) and David Harbour (Hopper) know their characters. Fans had been waiting for over five years to see their romance play out.

1 Eddie's Heart-Breaking Last Words Were Also Improvised By Joseph Quinn

Stranger Things' Eddie Munson in Season 4.

For any viewer who empathizes with their favorite fictional characters, the scene where Eddie Munson dies in Dustin's arms is sure to be tear-jerking. Even though many fans watched Volume 2 and expected the death of a major character, Eddie's demise was still tragic.

While Eddie's death is incredibly heartbreaking, one moment that particularly hammers this sentiment home is when Eddie says to Dustin, "I love you, man." It's relatively simple ad-libbed line, but the dialogue shows how Eddie thought of Dustin as a brother - a dynamic that Quinn really wanted to engrain in his character's final scene. Mike may be the heart of The Party, but this moment proves that Eddie was the heart of the Hellfire Club.

NEXT: 10 Times Stranger Things Season 4 Made Us Emotional