Airdate: Sunday.2.February.2003

CIA Agent Jim Lennox is in bed with his partner, Emma Wallace. She tells
him that she'd like to go back to Fiji. He agrees and they kiss. When he
goes into the shower, she frantically types an email: "Abort operation.
Lennox is a …" Lennox hits her before she completes the message. Sloane,
whom Lennox has called to say he'd been compromised, tells him to make it
public. Wallace, strapped with C-4, is thrown from a van onto a Berlin street.

In L.A., Vaughn tells Syd that Marshall and Dixon are being debriefed and
Sloane is now on Interpol's most wanted list. He also tells her that he
broke up with Alice. Weiss introduces Christine Phillips, a new
clandestine services grad from Langley who will observe for the next few
months. They all watch as Wallace appears on the news singing "Pop Goes
the Weasel." The agents watch in horror as Lennox remotely detonates the C-
4, killing Wallace.

Shortly thereafter Kendall briefs the staff, saying that Wallace's mission
had been to gain the trust of Dr. Enzo Markovic, a scientist developing a
technology known as Helix, to determine if it was a weapon. Enzo was
believed to have gone to a secret lab in the Serena del Sol Resort in Cayo
Cancho, off the Dominican Republic. Lennox is believed to be held there or
dead. Sydney and Vaughn's mission is to acquire intelligence and bring
Lennox back home.

Vaughn picks up Syd at her apartment. They kiss and she introduces him to
Francie, who thinks they're going to a finance conference in New York. Syd
gets a strange vibe from her.

At the resort, they force Enzo's security chief to reveal Lennox's
location. Syd interrupts Lennox's torture and beats his two inquisitors.
His eyes were affected so she blindfolds him and leads him away while
Vaughn acquires the Helix files. When Syd is attacked by a guard, Lennox
removes the bandage, risking his eyesight, to shoot him. Back home, the
CIA gives Lennox a clean bill of health

Under questioning, Lennox explains that while he and Wallace were working
for Enzo as freelance security experts, the discovered that he was working
for someone else. Lennox was going to hack the database in Cayo and
transmit the data to Wallace in Berlin, but he was caught before that
could happen. Sydney is shaken when he also reveals that he and Wallace were engaged.

Phillips analyzes the tape of Wallace's death and, due to static on the
tape, determines that the detonator was within a block of the explosion.A
sympathetic Syd visits the grieving Lennox at a safe house. He kisses her, vbut quickly apologizes.Two men appear and accost Lennox. He beats them but
then Syd subdues him because the men are government agents who want to
take Lennox into federal custody.

At the CIA, Jack reports that Helix is a new gene therapy that can reshape
a patient's face and body. The only way to determine an actual identity is
through an ocular scan — this flaw was purposely built into the procedure.
Lennox, he says, was the first test subject to be doubled, meaning Lennox
may actually be Enzo. Vaughn then places Lennox at the scene of Wallace's
murder. Syd is dubious, believing Lennox's grief to be authentic.

Lennox's scan checks out okay, and he's shocked when Syd tells him he's
been doubled. They learn that Enzo brought Helix to Poland. Syd and Lennox
are to find it, download the schematics and destroy it.

At a railroad depot, they disable the guards and break into the freight car
where the technology is hidden. Lennox reads data and learns that another
person has been doubled. Vaughn receives a frantic call from a man
claiming to be Lennox, who says the man the CIA rescued is really Enzo.
This Lennox says the ocular scan is merely disinformation and that he's
approaching the freight car and will destroy the technology.

Vaughn notifies Syd of the predicament. Jack tells her to disarm both men
and they'll figure out the mess once they're both in custody. She makes
Lennox handcuff himself to the freight car. When she leaves, he breaks his
hand in order to slip through the cuff and picks up a gun.

Syd confronts the second Lennox, but the first one appears. They're in a
standoff. Syd threatens to detonate Helix. The second Lennox reacts and
tries to shoot Sydney. The first — and real — Lennox shoots and kills the
phony. Sydney destroys Helix.

At the CIA, Lennox prepares to go to Fiji — he's never been there; he and
Emma were going to go on their honeymoon. Later on in Syd's apartment, she
and Vaughn fall into bed. But they're being observed through a camera
secretly installed in the television. Francie watches — she's the other double.