🚨Warning: There are spoilers ahead!🚨
1. First, on Stranger Things, part of Murray's conversation with Jonathan and Nancy at breakfast was improvised — you can even spot Natalia Dyer trying not to laugh.
2. Also on Stranger Things, the moment when Eleven collapsed into Mike's arms after battling Billy in the sauna was unscripted — Millie Bobby Brown was physically exhausted from filming the scene.
3. On Euphoria, the flashback that showed Rue fighting with her mom was completely improvised by Zendaya and Nika King — the script simply said "Rue and her mom have a fight."
4. On Brooklyn Nine-Nine, Captain Holt's iconic "hot damn" line was improvised by Andre Braugher.
5. On Schitt's Creek, Moira's iconic pronunciation of "bébé" was created by Catherine O'Hara while filming the scene for the first time.
6. On High School Musical: The Musical: The Series, Joshua Bassett actually came up with Ricky's monologue about loving Nini on the spot.
7. On Supernatural, Jensen Ackles spontaneously screamed Dean's classic "son of a bitch" line at the end of this scene — you can spot Jared Padalecki laughing in the final take.
8. On Parks and Rec, all the actors came up with their "drunk off Snake Juice" reactions on the spot — in fact, Amy Poehler was directing this scene and they were trying to make her laugh.
9. On Sex Education, Aimee Lou Wood hilariously improvised Aimee's "my ham" line after her sandwich was batted away.
10. On Grey's Anatomy, Jo kissing Arizona wasn't scripted and it was something Camilla Luddington came up with on the spot.
11. On New Girl, Max Greenfield improvised Schmidt's description of his dream girl during this flashback from the series finale.
12. On The Office, Steve Carell surprised Oscar Nunez by kissing him on the lips during the episode "Gay Witch Hunt." In the script, Michael was only supposed to kiss Oscar on the cheek.
13. Jason Segel didn't know Marshall's dad was going to die on How I Met Your Mother until they filmed the scene, so the final cut featured his genuine reaction.
14. On The Haunting of Hill House, when Theo and Shirley were startled by Nell's ghost in the car, the scene consists of Kate Siegel and Elizabeth Reaser's genuine reactions — Victoria Pedretti made her entrance sooner than they thought.
15. On Parenthood, Craig T. Nelson and Mae Whitman improvised the entire moment when Zeek took Amber to see her wrecked car after her horrific car crash.
16. On Riverdale, the moment when Kevin kissed Archie while performing "Tear Me Down" from Hedwig and the Angry Inch was unscripted — it was something Casey Cott and KJ Apa came up with while filming.
17. On One Tree Hill, during the series finale, Brooke's speech about what made high school so special was unscripted — Sophia Bush simply reminisced about her time on the show and playing Brooke.
18. On One Day At a Time, the moment when Lydia held Syd's hand after Elena explained that they were harassed after a date was improvised by Rita Moreno.
19. During The Vampire Diaries Season 5 finale, Ian Somerhalder added in the heartbreaking "baby" when Damon said goodbye to Elena before the Other Side collapsed.
20. On Veep, while improv was used a lot during preproduction, one moment that happened while filming was when Gary and Mike broke an expensive tea set in London.
21. On This Is Us, when Randall and William went to Memphis and visited a barber shop, their conversation was unscripted — Sterling K. Brown and Ron Cephas Jones simply talked about their real first haircuts.
22. On Dead to Me, Linda Cardellini came up with the heartbreaking line Judy uttered after learning Abe died in the moment.
23. And finally, on The Defenders, Krysten Ritter improvised this hilarious Jessica line when she saw Daredevil's outfit for the first time.
