As genre films go, "The Cabin in the Woods" is an all-timer.

Despite sitting on MGM's shelf for awhile, before Lionsgate stepped in to release it, Drew Goodard's directorial debut (which he co-wrote with Joss Whedon) paid homage to the horror movie genre while both satirizing and elevating the "final girl" tropes into one of the best, and most inventive, scary movies ever. Not bad for a film that they wrote a first draft of in three days.

As the fifth anniversary of our favorite "death by Merman"nears, here are a few things you might know about this genre classic. (And check out Film School Rejects for more trivia about the film.)
1. Goddard and Whedon co-wrote the film to make "something for us," according to the film's Blu-ray commentary. At the time, both had just come off feature film projects that didn't materialize. The two holed up in a hotel room and spent the weekend writing the first draft of the screenplay. They did a draft and then a polish later, before meeting with prospective companies and producers.

2. So why was "Cabin" delayed? It was tangled up in MGM's bankruptcy issues before Lionsgate rescued the film.
3. During the time that "Cabin" sat on a shelf, both its creators started to doubt the quality of their work. But, Lionsgate was so behind the film that it re-convinced Goddard and Whedon that it was a good movie.

4. One of the more problematic notes the filmmakers received was in regard to the film's opening scene. The studio thought opening with Bradley Whitford and Richard Jenkins doing a walk and talk through their Los Alamos-like facility would have confused the audience. "Opening the movie with this scene is one of my favorite things that we accomplished," says Whedon on the disc's commentary.
5. Goddardthought it would be a creative way to open the film, by intentionally making the audience think they had walked into the wrong movie.

6. Chris Hemsworth filmed the role of Curt about a year before "Thor" came out, according to Whedon on the film's commentary.
7. Shooting the scene where Hemsworth gives the group instructions (before crashing his motorcycle into a forcefield) marked the moment Goddard knew that Hemsworth was going to become a movie star.

8. After MGM saw the dallies of that scene, they signed Hemsworth to their "Red Dawn" remake. And then two days after that, the actor landed the role of Thor.
9. The first day of filming was at the gas station location where the group meets Mordecai, The Harbinger.

10. Goddard's first day filming was kind of a crappy one, logistics-wise. When he showed up to set, it was covered in snow (that's what he gets for shooting in Vancouver.)

11. Actors had to audition using scene specifically written for each character. Goddard notes on the film's commentary that The Harbinger (Tim De Zarn) was cast using a scene that had him fighting with a vending machine over a dollar while remarking on some pretty big, and kind of out there, existential ideas.
12. That thermal coffee mug/bong that stoner Marty (Fran Kranz) uses? It was a fully functional mug and bong combo which cost $5000 to make.

13. Goddard came this close to not directing the movie. The way Goddard remembers it, he and Whedon always planned for him to direct and Whedon to serve as producer. But according to Goddard, Whedon decided halfway through writing the screenplay that he wanted to direct the movie instead.
14. But, according to Whedon, Goddard's recollection can be filed under "wrong." Whedon argues that he and his co-writer did not know while writing it who would direct. In fact, the two bounced around potential names for director -- landing on Victor Salva of "Jeepers Creepers" fame.

15. The speaker phone scene, involving The Harbinger calling in to the control center, was the first scene the duo wrote after Whedon pitched the overall idea for the film.
16. A scene cut early in the development process (due to time) would have featured our main characters playing a game of "Truth or Dare or Lecture" while they were in the cabin. The game would have one person each take a turn to lecture someone else in the group about something they didn't like about them. The lecture cut from the script involved Marty getting the riot act about his excessive pot use. The line "I'm living in a womb of reefer" would have been a callback to this scene.

17. That long-ish scene in the control center, where people celebrate another successful sacrifice to the Ancient Ones? It came very close to being cut. The studio (MGM) wanted Goddard and Whedon to cut out most of it from the final film -- despite the scene perfectly setting up the third act.
18. Whedon eventually convinced his writing partner to cut the scene. So what did Goddard do? He broke down in front of him. After that, Whedon got on the phone with the studio and said they are not cutting the scene.

19. Another memorable sequence that was on the chopping block? The Japanese horror subplot. There were internal debates as to whether or not American audiences would understand the intent here. (Judging by the laughter in theater when I saw it, audiences understood it just fine.)
20. According to the director, the scene that tested highest with audiences was the Merman sequence.
21.Sigourney Weaver plays The Director, overseeing this night of deadly activity. The first question she had for her director once she arrived on set was "When will the werewolf be arriving?" The once and future Ripley was very eager to finally work with a werewolf. (She even mentioned to Goddard, according to the commentary, she was kind of bummed that -- when lunch came -- the actor in the werewolf costume was sitting alone.)
22. The film's final scene, written by Whedon, is meant to be his version of the "You always were an a**hole, Gorman" scene from James Cameron's "Aliens."