The Riim are a sapient telepathic species of vaguely avianoid humanoids which have been contacted at the farthest edges of the Milky Way. They are described as feminine-looking, although they truly have no gender and reproduce asexually by budding. They have golden feathers covering their entire bodies, except for the faces; and atrophied wings which are no longer usable for flight.
Their attempts at friendly contact with Humans accidentally resulted in great destruction, as they were unaware of the fundamental differences between the minds of two distinct sapient races. Their meddling with the minds of the Human crew of the Space Beagle caused the crew to become violently insane and hostile until Dr. Elliott Grosvenor was able to communicate with the Riim's hive mind and explain the situation.
- War of Nerves, by A. E. Van Vogt (1939)
- The Voyage of the Space Beagle, by A. E. Van Vogt (1950)
- Barlowe's Guide to Extraterrestrials, by Wayne Barlowe (1979)
- They are the only non-hostile species encountered by the Space Beagle.
- Their psychic approach and appearance are very loosely similar to the Ornithoid Lifeforms from the Star Trek episode "Cat's Paw".
- They are classified by the Beagle's anthropologist, Korita, as a fellahin-stage civilization, somewhat similar to the seemingly primitive Organians from the Star Trek episode "Errand of Mercy".