Eugen Vlacic

Eugen Vlacic is the son of Maria and Petro Vlacic.

Underground
Eugen is first seen leaving his apartment with his mother and father, shortly after Mishka Grenkov sent some of his men to murder Petro's family. Eugen was horrified after finding the thugs' corpses outside the front door, but Jack Bauer told him to ignore them and keep walking.

To ensure their safety, Bauer took Petro's family to one of his safe houses. While there, Eugen listened to his parents arguing with Jack about the whereabouts of his aunt, Sofiya. Shortly after Petro and Jack leave to go find Sofiya, Eugen heads into the bathroom and calls Agent Reese to let her know about Jack Bauer.

Reese and David show up at the safe house and question Maria and Eugen. Eugen confesses that he overheard Bauer talking to Grenkov and that he and Petro plan on heading to one of his warehouses. The CIA agents track down Sofiya and Mishka, while Maria and Eugen stay in the safe house.