"Thumbsucker" a teenage boy named Justin (Lou Taylor Pucci) who happens to have an oral obsession with his thumb. Justin’s mother Audrey Cobb (Tilda Swinton) is rather like Justin with obsessions all her own, like soap opera TV stars. The only normal person is Justin’s father Mike Cobb (Vincent D'Onofrio) and he is aware of Justin’s problem. Now Justin is enrolled in the debate workshop but can’t excel due to his oral fixation. So the parents send him to the dentist Perry Lyman (Keanu Reeves) who helps him cure his fixation with his thumb but now Justin’s teacher Mr. Geary (Vince Vaughn) believes Justin has Attention Deficit Disorder and sends him to the doctor where he’s given medicine which solves his thumb problem for good but makes Justin a hyper active genius.