“Smallville” actress Allison Mack looked glum as she headed into Brooklyn federal court Friday for a hearing over 
her alleged role in the twisted upstate sex cult Nxivm.
The 35-year-old, wearing black pants, a plum-colored blouse and a black cardigan, kept her eyes down and was escorted by her lawyer into court.
Her co-defendant, Keith Raniere, is expected to be arraigned on charges that he kept women as sex slaves and branded them with his initials as the leader of Nxivm.
Mack, who played Clark Kent’s pal Chloe Sullivan in the “Smallville” TV series, is charged with recruiting the women and grooming them for sex with Raniere. She’s out on bail.
Awaiting Raniere’s appearance in court was his ex-girlfriend of eight years, Toni Natalie, who blasted the cult leader as a “sociopath.”
“He said, ‘The next time I see you, you’ll be dead or in jail,’ ” Natalie recalled. Asked why, she said, “Because I left. He’s a sociopath.”
The 59-year-old woman dated Raniere from 1991 to ’99 and was only part of his cult in its nascent stages before she got out.
“When I saw the first Nxivm class, it was like a shutter shot,” said Natalie, who added that she had “hundreds” of sessions with Nancy Salzman, who created the self-help group with Raniere in 1998. “The whole thing made me uncomfortable.”