Watch: Sigourney Weaver explains vampire research from 'Nosferatu' to 'New Moon'

Last year, Sigourney Weaver was promoting "Avatar" at the San Diego Comic-Con, but she's had more than enough experience with some tough "Aliens" throughout her career. This year, though, she's touting spacemen of a different nature, in the forthcoming "love-letter" to the 'Con, Greg Mottola's "Paul."

Starring former zombie-hunters and comedy team Nick Frost and Simon Pegg, "Paul" features a much friendlier extraterrestrial, voiced by Seth Rogen. Weaver is mum on "what" she is the film, but only because it's a "big surprise" to come toward the end.

The actress not only has aliens in her future, but vampires and maybe even some ghosts. She's signed on to play the Vampire Queen in Amy Heckerling's 2011 comedy "Vamps," and she done her "research" in blood-sucking flicks, from "Nosferatu" to "New Moon." Plus, she tells HitFix, "I like meat, so it's gonna be alright."

So is there still the possibility of a "Ghostbusters III?" Weaver says, "I hope so, I get calls every now and then about it, but I'm busy doing other things" -- obviously. "I hope it comes together, but you never know in this business."

Check out why Weaver thinks Betty White is "this year's Tina Fey" and how she and Jamie Lee Curtis will play opposite of each other in "You Again."

"Paul" hits theaters March 18, 2011.