Whether it's to get around child labour laws or simply to make actual teenagers feel horribly inadequate, Hollywood has been casting adults as children for a worryingly long time.
Now that we're well past our high school days, we can still take comfort in these 30 actors who've managed to stick a well-paid finger up at the cruel beast that is age. There's hope for us all.
(Images: All Star, Rex Features, YouTube)
Cameron Frye (Ferris Bueller's Day Off)
Year: 1986
Played by: Alan Ruck
Character's Age:18
Real Age: 29
Betty Rizzo (Grease)
Year: 1978
Played by: Stockard Channing
Character's Age: 17
Real Age: 34
Napoleon Dynamite (Napoleon Dynamite)
Year: 2004
Played by: Jon Heder
Character's Age: 16
Real Age: 27
Ren McCormack (Footloose)
Year: 1984
Played by: Kevin Bacon
Character's Age: 17
Real Age: 26
Billy Loomis (Scream)
Year: 1996
Played by: Skeet Ulrich
Character's Age: 18
Real Age: 26
Michelle Flaherty (American Pie)
Year: 1999
Played by: Alyson Hannigan
Character's Age: 18
Real Age: 25
Denis Cooverman (I Love You Beth Cooper)
Year: 2009
Played by: Paul Rust
Character's Age: 18
Real Age: 28
Carrie White (Carrie)
Year: 1976
Played by: Sissy Spacek
Character's Age: 18
Real Age: 27
Peter Parker (Spider-Man)
Year: 2002
Played by: Tobey Maguire
Character's Age: 17
Real Age: 27
Cecile Caldwell (Cruel Intentions)
Year: 1999
Played by: Selma Blair
Character's Age: 16
Real Age: 26
Steve Andrews (The Blob)
Year: 1958
Played by: Steve McQueen
Character's Age: 16
Real Age: 28
Kelly Van Ryan (Wild Things)
Year: 1998
Played by: Denize Richards
Character's Age: 18
Real Age: 27
John Bender (The Breakfast Club)
Year: 1985
Played by: Judd Nelson
Character's Age: 17
Real Age: 26
Curt (American Graffiti)
Year: 1973
Played by: Richard Dreyfuss
Character's Age: 18
Real Age: 26
Regina George (Mean Girls)
Year: 2004
Played by: Rachel McAdams
Character's Age: 16
Real Age: 26
Jack Stall (A History Of Violence)
Year: 2005
Played by: Ashton Holmes
Character's Age: 16
Real Age: 27
Marty McFly (Back to the Future III)
Year: 1990
Played by: Michael J Fox
Character's Age: 17
Real Age: 29
Jess Kaur Bhamra (Bend It Like Beckham)
Year: 2002
Played by: Parminder Nagra
Character's Age: 18
Real Age: 27
Dionne Davenport (Clueless)
Year: 1995
Played by: Stacey Dash
Character's Age: 15
Real Age: 29
Frank Abagnale Jr (Catch Me If You Can)
Year: 2002
Played by: Leonardo DiCaprio
Character's Age: 16
Real Age: 28
Ted Stroehmann (There's Something About Mary)
Year: 1998
Played by: Ben Stiller
Character's Age: 16
Real Age: 33
Keith Nelson (Some Kind Of Wonderful)
Year: 1987
Played by: Eric Stoltz
Character's Age: 18
Real Age: 26
Julie (Jawbreaker)
Year: 1999
Played by: Rebecca Gayheart
Character's Age: 18
Real Age: 28
Daniel LaRusso (The Karate Kid III)
Year: 1989
Played by: Ralph Macchio
Character's Age: 18
Real Age: 28
Kim (Taken)
Year: 2008
Played by: Maggie Grace
Character's Age: 17
Real Age: 25
Han (Better Luck Tomorrow)
Year: 2002
Played by: Sung Kang
Character's Age: 18
Real Age: 29
Alan 'Mollymauk' Musgrave (Lord Love A Duck)
Year: 1966
Played by: Roddy McDowell
Character's Age: 18
Real Age: 37
Carter Horton (Final Destination)
Year: 2000
Played by: Kerr Smith
Character's Age: 18
Real Age: 28
Riff Randell (Rock N Roll High School)
Year: 1979
Played by: P.J. Soles
Character's Age: 18
Real Age: 29
Shawn Colfax (Fired Up!)
Year: 2009
Played by: Nicholas D'Agosto
Character's Age: 18
Real Age: 30