Planet 51

Movie review by
Sandie Angulo Chen, Common Sense Media
Planet 51 Movie Poster Image
Underwhelming alien comedy has some suggestive humor.
  • PG
  • 2009
  • 90 minutes

Parents say

age 7+
Based on 21 reviews

Kids say

age 8+
Based on 52 reviews

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A lot or a little?

The parents' guide to what's in this movie.

Educational Value
Positive Messages

Much of the positive stuff is secondary to the suggestive humor, but Lem and his friends do work together to help Chuck, and Chuck learns to trust the aliens, despite his initial hesitation.

Positive Role Models & Representations

Some characters are less than admirable, but Lem and Neera are positive role models: Lem takes a risk to trust Chuck, and Neera believes in peaceful protest to enact change.

Violence & Scariness

An alien general and soldiers try to take down the American astronaut with military weapons and guns. An alien doctor is after Chuck's brain -- for scientific reasons, of course...

Sexy Stuff

"Parking" aliens talk about how it's their first time "parking" (i.e. kissing in car). Two alien adolescents flirt with each other and eventually kiss. A female alien with robust cleavage gets angry at a male alien who's staring at her. A character makes repeated references to alien "probes" and how to discourage them. The astronaut tries to teach an alien how to romance "chicks." After seeing the astronaut naked (he drops his towel for a second, but the audience doesn't see anything), an alien jokes "that's a funny place for an antenna."


Mild language includes "what the...," "moron," and "stupid." There's also crass humor that includes commentary about  "chicks," "alien probes," and a  penis joke (the alien thinks it's an "antenna").


Twix candy bars, Sea Monkeys, and Volkswagen are recognizable/discussed brands. There's also an iPod-looking device and many obvious references to other movies.

Drinking, Drugs & Smoking

What parents need to know

Parents need to know that this animated alien comedy earns its PG rating with a fair bit of sexualized humor -- including jokes about anal probing and penises which may go over younger kids' head (though middle schoolers won't be duped -- in fact, they'll probably find it hilarious). There's also some mostly mild violence -- though weapons are involved -- as the alien army attempts to capture and subdue a human astronaut (voiced by Dwayne "The Rock" Johnson), as well as references to a maniacal doctor's desire to suck out Chuck's brain for scientific reasons. The language is mostly tame ("moron" and "stupid"), if disrespectful; beyond the sometimes-crude jokes, the sexuality revolves around one character's infatuation with another, which culminates in a kiss. Despite taking place on another planet, there are a few brands featured in the movie, including Volkswagen, Twix, and iPods.

User Reviews

  • Parents say
  • Kids say
Parent of an infant and 2-year-old Written bynearlyfallinstar May 16, 2011

More Worried About the Violence

I think the violence was a little too much for the younger crowd (if they would even pay attention to it). There is firepower with weapons and two aliens are di... Continue reading
Parent of a 6-year-old Written byHollyBolly March 5, 2011

Seriously?? In an animated movie?

I was really dissapointed with this movie. I did not check the rating before I let my son watch this since I assumed an animated movie would be safe. But when m... Continue reading
Teen, 14 years old Written byJessMBridgewood April 20, 2020

does anyone else only remember that one scene XD

this movie feels like a fever dream lmao
Teen, 13 years old Written bysgtsun May 29, 2019

i love it uwu

okay this came out when i was six, and now i'm thirteen. still love it. the reason why i say 10+ is because there is a lot of sexual stuff in it but 5-6th... Continue reading

What's the story?

On a distant planet that's exactly like an idealized version of 1950s America but inhabited by green aliens, adolescent Lem (voiced by Justin Long) works at a planetarium and spends his time hanging out with his best friend Skiff (Seann William Scott) and pining over his pretty neighbor Neera (Jessica Biel). When NASA astronaut Chuck Baker (Dwayne "The Rock" Johnson) lands on the planet, he's astounded to realize that there's already life on Planet 51 -- and that all the "aliens" speak and understand English and enjoy the diners, muscle cars, drive-ins, and B-movies reminiscent of the '50s. Unfortunately for Chuck, the most popular movie is about a "humaniac alien" that turns everyone into brainwashed zombies, so the planet's military tries to hunt Chuck down. But Lem and his pals strike up a friendship with Chuck and agree to help him get back to Earth before he's captured, studied, and imprisoned.

Is it any good?

Even if you take Pixar's incredibly sophisticated, high-grossing movies out of the running as a comparison, PLANET 51 is uninspired and forgettable. The movie's animation (particularly the landscape backgrounds) is flat, the dialogue is overly cluttered with pop culture references (to everything from The Right Stuff and E.T. to The Terminator and the Macarena). Allusions and double entendres work when they're seamlessly woven into a family-friendly script (as in the Shrek movies), but the lame penis and anal probing jokes are just off-putting in Planet 51.

Young kids may be drawn to the alien characters, especially comic book-obsessed Skiff and the dog-like creature that has toxic pee and a penchant for terrorizing the local mail carrier. And adults may get a laugh or two out of Neera's suitor Glar (Alan Marriott), a VW-van-driving, guitar-playing hippie who protests the planet's violent reaction to Chuck. But Johnson, who has proven he's a surprisingly talented family movie star, isn't given much to work with as the cocky astronaut, and Lem and Neera's "romance" is only slightly amusing when Lem goes to Chuck for dating advice. Ultimately, if you're hankering for '50s nostalgia, check out Back to the Future -- and for animated alien comedies, stick with Monsters vs. Aliens.

Talk to your kids about ...

  • Families can talk about how the movie plays on the media's standard jokes about and portrayal of aliens. Who is the "real" alien in Planet 51? How do the movies and comic books that characters read on Planet 51 affect the way its population reacts to Chuck?

  • What purpose do all of the pop culture references -- particularly to well-known movies -- serve? Is it funny? Is it original?

  • To what kind of movies is Planet 51 an homage? How are the '50s portrayed?

Movie details

Our editors recommend

For kids who love aliens

Themes & Topics

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