Alias - Season 4 Episode 12 -

Nadia puts her own life (as well Sydney's and Weiss's) in danger after failing to unveil her past about her involvement with a dangerous criminal, named Ceasar Martinez from her home in Argentina whom recruited her as an assassin for his gang and wants to relive old times. Meanwhile, Vaughn finds a person who is somehow connected to his father and Nadia as well.