Wednesday, Feb. 23
"Echoes"
With Nadia's life on the line, Sydney must race to bring down former nemesis Anna Espinosa (Gina Torres). Meanwhile, Vaughn's inner demons surface when, in order to help Sydney save Nadia, he's forced to confront his own former nemesis, the slippery and deadly Mr. Sark (David Anders).
http://abc.go.com/primetime/alias/