Keanu Reeves wants to save the planet, and he’s not talking about going green.

Reeves, who plays the alien Klaatu, the main character, alongside Jennifer Connelly and “Mad Men’s” Jon Hamm stars in the remake of the sci-fi classic, “The Day the Earth Stood Still.”

For Reeves, this is another sci-fi movie to add to his already numerous list, which includes but is not limited to, “Constantine,” “The Matrix” films, “A Scanner Darkly” and every stoner’s favorite, “Bill and Ted’s Excellent Adventure.”

“I love the genre,” said Reeves. “I grew up reading science fiction, watching science fiction films. I think it’s a wonderful genre in the sense that it’s a bit of a Trojan horse. Bit of drama, adventure — it’s also a great way to look at ourselves. It’s a genre that beautifully talks about our hopes, our fears, our anxieties, utilizing allegory, metaphor, in such a fantastic way.”

The original film, released in 1951, is a cult classic based on a short story by Harry Bates called “Farewell to the Master.” It has been updated for our modern times but still preserves the integrity of the original film.

“I think the film lends itself to that opportunity [for a remake] because of its timeliness, and because of how that could be translated to present day,” said Reeves.

“I hadn’t seen it, and a lot of people haven’t, I think,” said Jennifer Connelly, who plays Dr. Helen Benson.

“On that level, I think there is room to make another version of it,” Connelly said. “But I think it was just a really great story that’s a great template, and I think it was very much a movie of its time. No one was trying to fix that version.”

Though a predominately science fiction film, the cast insists there are factors that set apart this movie from the thousands of sci-fi films before it.

“There are some great visuals, but it’s also got some real, at the heart of it, personal relationships,” said Reeves.

“Jennifer Connelly is playing a scientist and also a mother, a stepmother, to a young boy, and they have their relationship,” he said. “The film is trying to work on a bunch of different levels. It’s kind of got big ideas, but it’s also got smaller kind of human stories to it.”

“I don’t know of any other movies out there that are really like it, to tell you the truth,” said Connelly.

“I think it brings more of the character of the original film … but I don’t know of any other movies that are out there like it. I think there is something special about it in that way, the way that it is a big, exciting kind of spectacle of a movie.”

Big-budget-movie newcomer Hamm said he didn’t find it difficult to transition from the small to big screen.

“Fundamentally, not much changes,” said Hamm, who plays Michael Granier. “It’s mostly just scale that changes, and that can be kind of overwhelming, speaking from totally personal experience, but it can also be sort of intensely cool and eye-opening and exciting.”