The animated 3-D movie Monsters vs. Aliens offers homages to many classic sci-fi movies of the 1950s, including The Fly, The Creature From the Black Lagoon, The Blob, Godzilla and Attack of the 50 Foot Woman, among others.

Cast members Kiefer Sutherland, Reese Witherspoon, Rainn Wilson, Will Arnett and Seth Rogen told SCI FI Wire that voicing the movie allowed them to rediscover and revisit their favorite B-movie creatures.

"For me, it's [Attack of the] Killer Tomatoes or The Blob," said Sutherland, who voices the loud-mouthed general who wrangles Earth's monsters. "What I think are fantastic about those films is that audiences are absolutely willing to suspend their disbelief. There's no way that you go to see The Blob or Attack of the Killer Tomatoes and not suspend your disbelief. I think that we live in a very kind of cynical world now. At that time it was very telling, in the '60s, where we're going to give that up and have a laugh and maybe get scared, and it'll be fantastic and be cool. There was this kind of willingness to surrender that kind of stuff then that I think is a little more difficult now."

Co-directors Rob Letterman and Conrad Vernon said they wanted to reacquaint audiences young and old with B horror movie monsters. "The idea came from watching old sci-fi horror that made us laugh and gave us cheap thrills," Vernon said. "We didn't just want to satirize those B-movie monsters, but wanted to give them personalities and come up with our own versions of them."

Take Dr. Cockroach—voiced by TV's House doctor, Hugh Laurie—a brilliant professor who tries to meld the survivability of roaches with humans but ends up turning his head into a bug's. There's also the 340-foot Insectosaurus, which is like a baby the size of Godzilla: He teethes on skyscrapers.

Then there's the Missing Link—half fish and half ape and voiced by Arnett. He said he liked John Carpenter's The Thing and the 1954 Creature From the Black Lagoon. "There are so many references in this movie that if you ever sat home on a Saturday afternoon and watched these old black-and-white movies on TV, then you'd remember them," he said. "Tarantula, Santa Claus Conquers the Martians, all of those."

Wilson, who voices Gallaxhar, a squidlike alien, said he grew up watching B movies "on weekends in the '70s, when they would replay The Blob and Godzilla and all those great classic horror movies. I loved it. I'm actually alien, so it worked out well. I would say that my favorite alien villain is the one from the Warner Brothers cartoon The Martian. Marvin the Martian is pretty great, although Gallaxhar is much more evil and macabre and seeking universal conquest, domination and annihilation. He just wants to be understood."

Witherspoon's character, Susan, is an average girl who gets hit by a meteor and grows 49 feet 11 inches tall, earning the nickname Ginormica. "I love those old movies, and I can't wait for my kids to see me in this one as this giant lady," Witherspoon said. She said she watched old Roger Corman horror movies with her father and personally liked Attack of the Killer Tomatoes.

Rogen plays a blob named B.O.B. that has no brains. "I was a fan of those movies from the '50s, but I was more insane for the movies of the '80s, like Army of Darkness and that kind of stuff," he said. "But I was always a fan of kind of the monsters movie genre."

Asked what he would do if actually came across a 49-foot-11-inch-tall woman, Rogan said, "I don't know what I'd do, but it would be something dirty, I'd bet that, something really dirty." Monsters vs. Aliens opens March 27.