Posted 1 hour agoSubscribe to Screen Time NewsletterCaret DownMadelyn Cline And KJ Apa Prove How Well They Know Each Other In This Hilariously Chaotic Costar TestNot Madelyn Cline making fun of KJ Apa's Archie from "Riverdale" hair.by Nora DominickBuzzFeed StaffFacebookPinterestLink Madelyn Cline and KJ Apa have both starred in two of the biggest teen TV shows in the last 10 years: Outer Banks and Riverdale. Monica Schipper / Getty Images, Stephane Cardinale / Corbis / Getty Images Now, the duo is teaming up for their new romance movie, The Map That Leads to You, which I can say with my whole heart that I loved so much. It might be one of the best young adult romance movies in recent years. Prime Video Based on the novel of the same name by J.P. Monninger, and directed by Lasse Hallström, the movie tells the story of Heather (Cline), who is traveling Europe with her best friends when she meets Jack (Apa). Soon, the duo embarks on a whirlwind summer of romance and travel together, with Jack visiting various locations his grandfather wrote about in a journal. Prime Video So, to celebrate their new movie, we had Madelyn and KJ take a costar test to see how well they really know each other behind the scenes, and it might be one of the most hilariously chaotic costar tests we've done. BuzzFeed Celeb / Via youtu.be Yes, out of the gate they had nicknames for each other. For starters, KJ felt extremely confident that he knew the first time he met Madelyn, but she quickly pointed out that he was wrong and they actually met at a gym years prior. BuzzFeed Celeb / Via youtu.be They also agreed on their favorite behind-the-scenes memory from filming The Map That Leads to You, which was when one of their security guards "almost decked a guy." BuzzFeed Celeb / Via youtu.be And while they didn't know everything about each other, like what Madelyn's go-to snack at craft services was, the whole thing was just so delightful because they love to goof around together. BuzzFeed Celeb / Via youtu.be Like, I genuinely have not seen costars make each other laugh so much in a long time. BuzzFeed Celeb / Via youtu.be You can check out Madelyn and KJ's full costar test below: View this video on YouTube BuzzFeed Celeb / Via youtu.be And be sure to watch The Map That Leads to You, which is streaming now on Prime Video. Prime Video