Infamous

'While researching his book In Cold Blood, writer Truman Capote develops a close relationship with convicted murderers Dick Hickock and Perry Smith.'

Infamous is a 2006 American drama film written and directed by Douglas McGrath. The screenplay, based on the 1997 book Capote: In Which Various Friends, Enemies, Acquaintances and Detractors Recall His Turbulent Career by George Plimpton, covers the period from the late 1950s through the mid-1960s during which Truman Capote researched and wrote his bestseller In Cold Blood, a subject covered in the film Capote a year earlier.

Source: Wikipedia