One of the alien intellects of the Think Tank, the group of problem-solvers led in negotiations by Kurros, whose unusual speech must be interpreted for outsiders in the episode Think Tank.
Fennim appears in the Voyager episode Think Tank. He belongs to a small group of brilliant beings from different species who live aboard a hidden ship and solve other civilisations' problems in return for a price of their own choosing.
Fennim's language cannot be handled by Voyager's universal translator, so the group's spokesman Kurros relays what he says. The members stay in constant contact with one another through a telepathic link.
When Janeway discovers that the Think Tank arranged for the Hazari to hunt Voyager in order to obtain Seven of Nine, she turns the scheme against them. Their link is disrupted, and Fennim and the others are left exposed to the Hazari.