->'''Perry''': There's only so much I can do with traditional orthodontics. Justin, are you ready to let go of your thumb?\\
'''Justin''': Why are you talking like that?\\

''Thumbsucker'' is a 2005 American comedy-drama film directed by Mike Mills and adapted from the Walter Kirn novel of the same name. The movie focuses on teenager Justin Cobb as he copes with his thumb-sucking problem, and on his experiments with hypnosis, sex, and drugs.

!!This movie provides examples of:

* AnimalMotif: Justin’s “power animal” is a deer. Implied that Perry’s is a wolf.
* AnnoyingYoungerSibling: Joel.
* AttentionDeficitOohShiny: Justin gets diagnosed with ADHD, put on medication, and we get a little montage of the way it affects him, such as high detail zoom-ins on the words and pictures when he reads ''Literature/MobyDick''.
* ComingOfAgeStory
* DeadpanSnarker: Justin, at times.
* EatingLunchAlone: Or: Sucking Your Thumb Alone in the Bathroom During Lunch.
* TheFilmOfTheBook
* GrowingUpSucks: Or more accurately "Getting Old Sucks." A major theme is the adult characters' desperate attempts at staying young, Justin's mother Audrey most of all.
* JukeboxMusical: In the sense that all the music in the film is done by Tim [=DeLaughter=] and The Polyphonic Spree.
* ImagineSpot
* InWithTheInCrowd: With the debate team, after Justin starts taking medication.
* ItWasWithYouAllAlong: [[spoiler: There are no physical or emotional effects from sucking your thumb, Perry says.]]
* OneWordTitle
* PopStarComposer: Music/ThePolyphonicSpree, with some posthumous cover songs by Music/ElliottSmith make up the soundtrack.
* TheQuietOne / LonersAreFreaks: Justin.
* TheStoner: [[spoiler: Rebecca's group after she leaves the debate team.]]
* ThrowItIn: Justin's reaction to [[spoiler: Rebecca "breaking up" with him]] was ad-libbed by Lou Pucci.
* TrailersAlwaysSpoil: The DVD blurb pretty much tells you the entire film.
* WildTeenParty: Briefly, in the hotel room at the debate regionals.