With the first episode of Firefly, Joss Whedon knew he had to wow the audience and quickly establish his sci-fi western as something totally original. So, naturally, he threw in an Easter egg into the pilot that suggested Firefly and Alien take place in the same world. We know this from a scene where Mal, the future captain of the Serenity (which, by the way, also had a cameo on Battlestar Galactica), uses a gun turret bearing the logo of the Weyland-Yutani Corporation.
Weyland-Yutani were of course the owners of the Nostromo ship from the first Alien movie, and the subsequent a-holes who took one look at the titular acid-blooded perfect killing machine and thought to themselves: “We should throw that at the people we don’t like until they go away.”
Interestingly, they were also the a-holes represented by the Wolfram & Hart demonic lawyers in Angel, the sequel to Buffy the Vampire Slayer. And if that sounds like the most bizarre pop culture connection ever, then wait until we tell you that Xenomorphs also appear in Star Wars novels and comic books. Oh, we guess we just did.
Finally, the Star Wars connection helps link everything to Star Trek and Indiana Jones, as R2-D2 has a cameo in J.J. Abrams’ first Star Trek movie, and in Raiders of the Lost Ark.