[O]ne thing defines [Seska] in contrast to the Cardassians we’d been regularly seeing on Star Trek at that moment in time: she’s just kind of an absolute hot mess.
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But it’s kind of what makes Seska work as a character: despite all this, villainy or otherwise, nothing ever quite clicks for her. It’s a great mirror to uphold against Janeway’s decision to have the crew take the long way home in the first place, the idea that, if they did ultimately just go Seska’s route and exploit their advantageous power in an unknown quadrant, it would doom them.
I think my two favorite Seska episodes were the ones after she was dead. The one with Tuvok’s hacked security training program / holonovel and then “Shattered”. She just seemed way more cunning and dangerous in those two than she ever did when she was allied with the Kazon (“Shattered” notwithstanding).