Alias - Season 4 - Eps 8: Echoes
Sloane temporarily steps down as Director of his Task Force and gives Jack full authority over the next assignment, which involves Anna Espinosa, Sydney's old foe. However, Anna turns the tables on APO when she captures Nadia and forces Sydney to do her biddings. Sydney tells Nadia about the Rambaldi's prophecy which dictates that two sisters will fight and only one will survive. Meanwhile, Vaughn visits Sark and tries to trick him into helping them to catch Anna. In the end, one of the sisters is mortally wounded by Anna.
About Alias

Title: Alias
First Air Date: 2001-09-30
Last Air Date: 2006-05-22
Status: Ended
Rating: 6.736/10 (from 645 votes)
Language: EN
Seasons: 6
Total Episodes: 105
Network: ABC
Genres: Action & Adventure, Drama
Production Companies: Bad Robot, Touchstone Television
Synopsis
Sydney Bristow, an agent who has been tricked to believe she is working for the U.S. government, is actually working for a criminal organization named the Alliance of Twelve. Upon learning this, Sydney becomes a double agent for the real CIA.
Cast

Jennifer Garner
Sydney Bristow

Michael Vartan
Michael Vaughn

Victor Garber
Jack Bristow

Ron Rifkin
Arvin Sloane

Carl Lumbly
Marcus Dixon

Kevin Weisman
Marshall Flinkman

Rachel Nichols
Rachel Gibson

Amy Acker
Kelly Peyton