Villain Manifesto - Inspector Kashyk
Inspector Kashyk first comes aboard Voyager in a security sweep - searching Voyager for telepaths (forbidden by the Devore Imperium). He is handsome, smooth, has taste in music and is in all other ways slightly too good to be true! (My favourite kind of villain!) There is tension on the ship, as they are in fact hiding a shuttleload of fugitive Brenari telepaths, in addition to the Vulcans and other telepaths of the crew.
Inspector Kashyk investigated Voyager a few more times than strictly necessary, and ingratiated himself with Captain Janeway. He confided in her that he was having doubts about the Imperium's stance on renegade telepaths, and asked for her help in defecting. In exchange, he offered to help her avoid Devore security. They work together on detecting the moving wormhole which the telepaths need to escape beyond Devore space, and forge a close working relationship. Eventually they find the solution together.
He also decides to ingratiate himself with Captain Janeway a little more directly...
However, the escape of the refugees looks about to be foiled by one last Devore inspection. Kashyk volunteers himself to go back to the Imperium and resume playing his role as an Inspector in order to protect them all. Janeway agrees, and the next time they meet he is once again the Inspector at the head of a hostile alien security force.
But instead of helping Voyager and the refugees escape, he uses the knowledge he discovered in concert with Captain Janeway to destroy the wormhole and reveal the secret hiding place of the refugees - only to discover that Captain Janeway never truly trusted him. The refugees have already escaped through the wormhole and Kashyk's betrayal has accomplished nothing but her triumph.
Kashyk is, at the last, a gracious loser. He congratulates Captain Janeway on out-manoeuvering him and beating him at his own game. He forgoes revenge in a salute to an honourable enemy, and lets Voyager leave Devore space unmolested. Captain Janeway tells him that she never lied to him and that her offer of asylum and a place on Voyager's crew was genuine. He smiles ruefully - admits it is a tempting offer, but despite the potential of their relationship, not one he was ever truly going to let himself accept. To the end, he is an officer and a gentleman! ANd I'm pretty sure Janeway had a soft spot for him too...
(Kate Mulgrew later chose this episode as her favourite, particularly reminiscing about the chemistry between herself and Mark Harelik - which is, IMHO, clearly evident and why this episode is also one of MY favourites!)