Hellspark is a delightful first-contact murder mystery by Janet Kagan, author of the Star Trek novel Uhura's Song. The members of the survey team on the newly discovered planet Flashfever are at each other's throats. Both the local wildlife and the local weather keep trying to zap them. No one can tell if the indigenous creatures named "sprookjes" are sapient, because they insist on parrotting the surveyors' attempts at communication. The surveyors themselves, all from different civilizations, keep stepping on one another's cultural toes. When a member of the team is found dead, no one knows whether he was killed by a sprookje or another surveyor; and the implications are unpleasant either way.

Enter Tocohl Susumo, one of the interstellar traders known as Hellsparks. Hellsparks are cultural chameleons, fluent in not just the spoken language but also body language, customs, and taboos of the many planets where they trade. One of the surveyors hires Tochol to learn the sprookjes' language, if they have one. She soon finds herself embroiled in the murder investigation and in considerable danger of her own.

Tocohl Susumo is an instantly likable heroine, flamboyant and self-assured. Her mouthy ship's computer, Maggy, is one of the most endearing AIs in science fiction. The supporting characters are well-drawn and memorable, and the dialogue is full of the barbed verbal interplay that Lois McMaster Bujold does so well. Flashfever itself is an electrician's nightmare, with an ecology in which most of the flora either feed on electric charge or generate it.

Kagan leans heavily on the body language gimmick, but as gimmicks go, it's a good one. Hellspark is an interesting examination of how culture shapes language, and how language shapes thought. It's inventive, fast-paced, and as cheerful a story as a murder mystery possibly can be.