Seska was a Cardassian operative who had been posing as a Bajoran in order to infiltrate the Maquis, and her holographic counterpart was part of a popular holonovel in Star Trek: Voyager season 3, episode 25, "Worst Case Scenario". The holodeck program about a Maquis insurgency aboard Voyager turned out to be a training program that security officer Lt. Tuvok (Tim Russ) had written shortly after Voyager's initial stranding in the Delta Quadrant. The purpose of the program was to for all potential possibilities should the Maquis crew actually attempt mutiny, and Tuvok included several actual Voyager crew as holograms within the program, including Seska.

Why Voyager's Seska Hologram Wasn't In Star Trek: Lower Decks Season 4

Star Trek: Voyager's Seska hologram wasn't included among Voyager's holographic villains in Star Trek: Lower Decks because she was a Starfleet security risk. Tuvok's training program was unfinished, but so popular among the Voyager crew as a work of fiction that he and Lt. Tom Paris (Robert Duncan McNeill) opted to reactivate the program to complete it. When they opened the file to make changes, the holodeck's safety protocols disengaged, the scene around Tuvok and Paris shifted to Voyager's brig, and a holographic version of Seska materialized to let them know that she had made some changes to the program prior to her departure.

The real Seska had died a year earlier, leading the Kazon in an attempt to retake Voyager by force, so the hologram she'd planted was a little treat left behind for Starfleet officers to discover. She'd turned the exercise into a genuinely dangerous holodeck program, and her character could shut down holodeck saftey protocols, comm systems, transporters, and link holodeck controls with booby traps throughout the ship. She'd even been able to control other holograms, like the Doctor (Robert Picardo). Activating her had led to actual mortal danger for not just Tuvok and Paris, but everyone else aboard Voyager. Anyone accessing her program would be subject to the same conditions, so a thorough security officer like Tuvok would reasonably delete it.

Seska Was Worse Than Voyager's 3 Hologram Villains In Lower Decks

In Star Trek: Lower Decks, Rigelian curator Beljo Tweekle (Andy Richter) included the holographic characters of Doctor Chaotica, Michael Sullivan, and the Clown in his USS Voyager museum exhibit, but none of them were as dangerous as Seska. Chaotica was melodramatic, but hardly a real threat, and Michael just longed for romance. The Clown was arguably the worst, but he hadn't been an actual holodeck program so lacked the life-threatening power of the real thing, which came from his original computer. Their ability to take over Voyager came from the combined influence of reactivated Borg nanoprobes and the Tak Takian Macrovirus, and wasn't inherent to their programming.

If the Seska hologram had remained within Voyager's computer, she could have certainly taken over all of Voyager's systems singlehandedly, leaving Tweekle and the Cerritos crew no recourse in her grand revenge. Tweekle's additional holoemitters would have given her full access, so she couldn't have been defeated by killing her within the program, as Tuvok had done. Her programming made her indistinguishable in personality from the real Seska, who harbored genuine malice towards Voyager and its crew. No doubt Star Trek: Lower Decks could have handled her reappearance with its usual comedy, but there's no reason to believe Lt. Tuvok wouldn't have deleted such a dangerous program.

Star Trek: Lower Decks season 4 is streaming on Paramount+.