Who he is: Fictional German P.O.W. camp colonel from '60s TV series "Hogan's Heroes."
Identifying marks: Groove in upper left cheek from monocle.
Homer's obsession: Loves to taunt Klink with knowledge of secret antics by Hogan and his men.
True identity: Sir Isaac Newton.
Reason for charade: To appear as someone Homer would recognize and revere.
[Caption of Homer at the bottom of the page saying "Colonel Klink! Why have you forsaken me?"]