One of the best of the hundreds of Star Trek novels published. A rare story of Uhura (who falls in love!), who with Kirk and Spock are attempting to save the Taygetians, semi-aquatic singing creatures killed for the jewel-like tears they secrete at the moment of death. These Taygetians can be compared to our humpback whales - creating a parallel with the Star Trek "San Francisco"-based film about saving the humpback whales. A very enjoyable read.