Star Trek Beyond: 25 Easter Eggs, References & In-Jokes

After it is revealed that Kirk hid the artefact from Krall by putting it literally inside the head of Ensign Syl, she is forced to give up the weapon when the villain tortures Sulu.

The way her head opens up (which is disgusting, let's be frank), is VERY reminiscent of the design of an Alien face-hugger. The "legs" are almost certainly exactly the same. That can't be accidental.

Krall too owes his design to a classic film: since he is basically a vampire, it's a lot easier to see that his pointed ears, teeth and general facial design (without the ridges) have come from Count Orlok.