In September 1999, the raunchy teen filmAmerican Piewas released.

The comedy, starring Jason Biggs, Seann William Scott, Alyson Hannigan and Tara Reid quickly became an international success and was followed by three more films; which combined made $989.5 million at the worldwide box office.

Crazy.

Watch the trailer for American Pie here. Post continues below.

But what's more crazy is that it's been 21 years since the first film was released.

Here's what the teenagers fromAmerican Piehave been up to since.

Jason Biggs (Jim Levenstein)

Jason Biggs played awkward and naïve protagonist Jim Levenstein.

Now, Biggs has appeared in plenty more acting roles.

He played Piper's husband in Orange is the New Black and starred in films includingSaving Silverman,Over Her Dead BodyandMy Best Friend's Girl.

He's currently playing the main role of Mike in the sitcomOutmatched.

In 2008, Biggs married hisMy Best Friend's Girlco-star Jenny Mollen. They have two sons, Sid and Lazlo.

Alyson Hannigan (Michelle Flaherty)

Alyson Hannigan played Michelle Flaherty - the band geek who went to prom with Jim and later became his girlfriend and wife.

After the first threeAmerican Piefilms wrapped, Hannigan landed her other most memorable role: playing Lily on How I Met Your Mother .She played that role for nine years.

In 2003, Hannigan married herBuffy the Vampire SlayerandAngelco-star Alexis Denisof.

They have two daughters, Satyana and Keeva Jane.

Chris Klein (Chris 'Oz' Ostreicher)

Chris Klein played the kind-hearted star athlete 'Oz'.

Since those days, Klein has appeared in various films including Mel Gibson'sWe Were Soldiersand more teen movies includingJust FriendsandAmerican Dreamz.

He's currently playing Bill Townsend onSweet Magnolias.

Personally, Klein started dating Katie Holmes in 2000. The couple became engaged in 2003. But sadly, two years later they called it quits.

In 2005 and 2010, Klein was arrested for drunk driving. In 2010, he checked himself into a rehabilitation centre, to begin an alcohol addiction program.

"I would have died, and I think about that every single day," the actor told People in 2012.

"It got to the point where I was a fragile shadow of the young man that came into this business. Today, I’m the luckiest guy alive."

In 2015, Klein married real estate agent Laina Rose Thyfault. They have two children.