S3, E10: The identity of the mysterious St Aidan forces Sydney to pull a stunned Will out of witness protection, but the pursuit sends the two old friends on a collision course with Allison - the woman who ruined both their lives. Lindsey arrests Jack and Vaughn as conspirators in Sydney's escape from NSC custody. Sloane puts a plan in motion to eliminate Sydney. Dr Brezzel has a run-in with Sark.