After CIA agent Emma Wallace (Olivia D'Abo) is killed in full view of a nationwide TV audience, Sydney (Jennifer Garner) and Vaughn (Michael Vartan) are assigned to take over Emma's mission. They must determine if a new gene-splicing technology called Helix is actually some sort of weapon -- and they must also locate Emma's CIA partner, Jim Lennox (Ethan Hawke). What they do not know (but the viewer does) is that the man calling himself Lennox is a double agent. Meanwhile, the evil lookalike of the murdered Francie (Merrin Dungey) -- one of the earliest "customers" of the Helix -- makes her first move. ~ Hal Erickson, Rovi