It's appropriate that the mind-bending thriller "Inception" (which opens today) is about dreams, because one of its stars has been visiting ours for years. While Leonardo DiCaprio may get top billing, his equally dreamy costar Joseph Gordon-Levitt has certainly been giving fans some pleasant thoughts for years.

(Click on the photo below to see JGL throughout the years and keep reading to follow the evolution of one of Hollywood's brightest young stars.)

The 29-year-old cutie, who got his start way back in the 90s alien-sitcom "3rd Rock From the Sun," has come a long way transitioning from teen heartthrob ("10 Things I Hate About You") to respected indie actor ("(500) Days of Summer").

Joseph Leonard Gordon-Levitt was born in Los Angeles. Not unlike his "Inception" co-star, Leo, Joseph got bit by the acting bug at a very young age. Also like Leo, he got his start on TV (making his small-screen debut in a movie called "Stranger On My Land" at the age of 7) but eventually transitioned into movies. In 1992, at the young age of 11, Joseph made an appearance in a film called "A River Runs Through It" (a movie starring none other than Brad Pitt!)

While he continued to have bit parts on television ("Roseanne," "The Powers That Be") and movies ("Angels in the Outfield," "The Juror") the rising star's big break came when he played Tommy Soloman, a super intelligent alien living on Earth as a human teen (not to mention sporting some major 90s hair) on "3rd Rock." The Emmy-winning series (which ran until 2001) opened the door for Joseph to star in more projects.

In 1998, Joseph starred in the horror flick, "Halloween H20: 20 Years Later," and a year later won over countless fans with the beloved comedy "10 Things I Hate About You." After appearing in mainstream features, Joseph opted to take the indie route for a while. The actor won over critics with his work in smaller, but well received films, such as "Brick," "Stop-Loss" and "The Lookout" (The Village Voice declared that JGL's performance was "worth the admission.")

While 2009 gave us one of the actor's worst reviewed movies (not to mention one of the worst movies of that year) with "GI Joe: Rise of the Cobra," all was forgiven with hit dramedy "(500) Days of Summer." As lovelorn Tom, Joe perfectly pegged what it's like to find bliss with another person (cue Hall and Oates!), but really the excruciating pain that comes with the fallout of a relationship (especially when it's with Zooey Deschanel.) The movie was a smash and Joseph's nuanced performance didn't go unnoticed, as he earned a Golden Globe nomination for Best Performance by an Actor. Later that year he earned another huge accolade and hosted "Saturday Night Live".

In an industry where child stars crash and burn in a very public way, JGL has managed to stay out of the tabloids and do work that he believes in. If anything, "Inception" will open the talented star to an even bigger audience, but we've known all along that he was someone to watch.