05/04/2012 11:53 am ET Updated Dec 06, 2017

Robert Downey Jr.: 'The Avengers' Star Then And Now (PHOTOS)

Before he was Iron Man, "Avengers" star Robert Downey Jr. was a student at Santa Monica High School in California. Not long after this picture was taken, Downey dropped out of high school and moved to back home to New York City to pursue acting.

After a short stint on "Saturday Night Live," the actor starred in a few Brat Pack movies, including "The Pick-Up Artist," opposite teen queen Molly Ringwald. However, Downey soon became notorious for his struggles with substance abuse. He was arrested several times from 1996 to 2001.

Thankfully, after years of treatment and relapse, Downey finally cleaned up his act. In 2008, he starred as billionaire genius Tony Stark in Marvel's "Iron Man," and it was the critical and commercial success that put Downey -- and Marvel's "Avengers" -- back on the map.

However, some things never change. If you look closely at 17-year-old Downey Jr. below, you'll see that even before the fame, he was sporting his signature smirk.

See the entire gallery of "Avengers" stars before they were famous at Snakkle.com.

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