Infuriated by Carter's lack of understanding of Rambaldi's "true" purpose, Sloane snaps. He yells that Carter is "unworthy" and proceeds to with a metal bar. The episode ends on a chilling note when Nadia enters the lab to find her father standing over the bloody corpse, his face splattered with blood, calmly telling her, "It's all over, honey". "Alias" Another Mister Sloane (TV Episode 2005) - IMDb

The story begins in Krakow, Poland, where a nuclear physicist named is kidnapped by men posing as airport security. She is brought to a dark room where she is greeted by a man who looks exactly like Arvin Sloane —later jokingly referred to by fans as "Arvin Clone". Meanwhile, in Los Angeles:

Jack eventually realizes that someone is meticulously framing Sloane. To clear his name and stop the imposter, the real Arvin Sloane must join the APO team on a mission to track down his double.