- Siblings: Irina Derevko (deceased), Katya Derevko
- Nieces: Sydney Bristow, Nadia Santos (deceased)
- Grandnieces & nephews: Isabelle Vaughn, Jack Vaughn
Before Season 4
Elena was one of the KGB's foremost assassins, responsible for the murder of countless diplomats and politicians throughout Eastern Europe. Thirty years before Season 4, Elena disappeared and could not be found even by her sister Irina (A Clean Conscience).
Little did they realise that Elena had posed as "Sophia Vargas", the head of the orphanage Nadia Santos, her niece, was at.
Around a year before Season 4, Arvin Sloane and Jack Bristow had been investigating the whereabouts of Elena. Jack received a message from an old associate that led him to one of Elena's safehouses in Warsaw. Inside was detailed information on the lives of Sydney Bristow and Nadia Santos, her nieces, with evidence suggesting she had them under surveillance for at least a decade. They assumed she was responsible for the attack on "Sophia", not realising that she in fact was Sophia (A Clean Conscience).
Elena arrived in Los Angeles, disguised as "Sophie Vargas". She used her former connection to Nadia to stay with her and Sydney so as to monitor their work for the CIA. She claimed to have been attacked in her home in Argentina, the reason for her coming to the United States. She gave Nadia a necklace with St. Marcos on it, who Nadia's orphanage was named after. Nadia took it, but did not know that Elena had implanted a microphone into the necklace so she could monitor Nadia's conversations and CIA work (A Clean Conscience).
She later offered to cook dinner for Sydney, Vaughn, Nadia and Weiss. Sydney and Vaughn were unable to make it because of Jack's illness, so only Nadia and Weiss attended. Elena took the opportunity to have her associate, Avian, hack into Nadia's laptop and request to move the Hydrosek, a deadly weapon, to an unsecured location away from APO. Elena and Avian then went to the site and stole the weapon before Nadia and Weiss could arrive to stop them - albeit not realising who it was that stole it (Mirage).