Palm Springs).

Egged on by their new friends, Marcus and Emily engage in all sorts of new activities they never would have dreamed of in their previously steadfast life. But when said friends try to break out of their vacation box and enter the real world, the more uptight duo must figure out how to handle life's latest curveball. All of that's on top of the stress already placed on them by Emily's disapproving family, making for one eventful wedding.

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Director and co-writer Clay Tarver (who previously worked on Silicon Valley) spoke with Screen Rant about what made the cast so perfect for their roles, and how some of his dicey directorial choices paid off in the end.

Marcus and Emily walk into the Caribbean resort.

Screen Rant: What was it that made these actors right for those parts? Because they have so much chemistry that you could have just switched any of them to play anyone else.

Clay Tarver: Yes. Rel, when I first met him, it was pretty remarkable because it was almost like we'd written the part for him already. He's from Chicago; he's from the tough part of town, and he's tough. But he's also kind of a nerd in the tough neighborhood - and he would it it. He's not as controlling and uptight, and he is different, but the main things about his energy really fit well with that character. And it was that weird thing of like, "Man, I felt like I helped to rewrite and put it together for someone I hadn't even met yet. And here's the guy."

And Yvonne was sort of the same thing. She's so funny, and she's so gifted as a comedic actor, but she also has this elegance and ease about her. And they had known each other for years and years and years, so they felt like a real couple.

John was just... I had no idea how good he was and how gifted he was as a performer. He just played a part that was so built for his body and his instrument. It was really fun to work with him on it, and he's such a great listener and plays off people so much more than you would think.

And Meredith Hagner? I loved her work in Search Party. We really read a lot of actresses for that, and she just demanded [attention]. Her performance was so spot-on, and she was like, "I am that person! I would say that. I would get in trouble on a vacation if you came with me."

In the end, it just felt like here are two couples [that] have known each other forever, and they meet. I was blessed, believe me. I was sitting there going, "I don't know how I ended up this lucky." Because so much of it is just getting good people who are right for the parts.

On the directorial side of things, there are some sequences that are just fabulous. Without spoilers, there's the fox chase, and then the return of the bird. What was the process behind deciding how to show those?

Clay Tarver: They were a little bit of a leap of faith because there's a lot of visual effects that won't come back in for months and months. Like anything in a movie, you're shooting it with Rel rolling around with a very small woman in a blue suit, going, "I hope this works." And you turn to the visual effects supervisors, who's there, like, "Is this gonna work?" He's like, "...Yeah!" and you're like, "I hope so."

When we shot the second bird sequence, I thinking, "Wow, was this the worst idea ever to have?" But there's so many talented visual effects people working on the movie that, by the end, I was so glad I took that chance.

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Vacation Friends drops August 27 on Hulu.