“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.