Salvatore Mancuso returns to Colombia after 15 years in a U.S. prison.

He is accused of ordering massacres, homicides, disappearances, kidnappings and displacements. He has admitted to hundreds of crimes and has accused politicians, businessmen and soldiers of having helped him. The man whose return paralyzes Colombia came to paramilitarism in the 1990s through the Convivir, the initially legal ranchers' associations that sought to protect themselves from extortion and attacks by guerrillas.