Dixon assigns a reluctant Syd to be Sloane's handler and says Allison Doren is alive. An unnerved Syd later says she will kill Allison. Sark meets Allison in Strassburg, rekindling their love. Allison explains that The Covenant found her and Syd after their fight. She recovered in 6 months and has been working for them since. Sark says will find his father's murderer and Allison swears Syd will pay for her scars.

Lindsay tells Lauren that a Russian government source has info that could lead to Lazarey's murder and that The Covenant has moles in the Russian government. He swears Lauren to secrecy and sends her to meet the source in Moscow. Lauren lies to Vaughn about the trip. He gives Lauren a database of Lazarey's phone calls, suggesting the murderer may be traced through calls.

In Milan, Syd is disguised as a Euro clubber. Vaughn uses a Marshall-made mini x-ray camera, rigged via Syd's necklace, which can spot facial reconstruction. Sark and Allison appear. Lang retrieves his papers and bolts when Allison kills Strauss. They all chase Lang, but Allison finds him first and extracts a tooth before killing him. Syd discovers the body, whereupon Allison knocks her unconscious.

Back at the CIA, the x-ray images of Lang's tooth reveal a filling that is a Radio Frequency Identification chip. Lang used the chip to open the launching device. Lauren discovers a call from Lazarey's murderer and tracks it, through voice analysis, to the London address KNG Microtech. The office is empty but Lauren discovers it was leased to Julia Thorne.

Syd forces Sloane to meet with Sark and Allison in Prague and get them to divulge the location of the device. Using his cover as a double-agent, Sloane coaxes Sloane to admitting the device is in a vault in Sophia, Bulgaria. Syd makes Sloane ask about her past. Allison says The Covenant ordered her not to kill Syd because they want to retrieve something her memory. This makes Syd want to undergo CIA memory retrieval, which Jack vehemently opposes.

Dixon sends Vaughn and Syd to Sofia. He privately admits to Syd that he wants Allison dead because she murdered his wife. Using a tracking device, Syd and Vaughn find Allison in an abandoned building in Sofia and give chase. Allison corners Syd and says that Syd had discovered a formula for a medication in the Rambaldi journal — which was ultimately used to heal Allison's wounds. Syd grabs Allison's gun and shoots. She alive, but barely. They find the device on her body.

Syd's suspicions are raised when Vaughn knows nothing about the formula. They find the ambulance overturned, the medics dead and Allison missing.