The HHV Rhev was a Hirogen warship in service in the late 24th century. In 2376, the Rhev joined a multispecies caravan to cross the dangerous No Man's Land region of space. (VOY - Gateways novel: No Man's Land)
Around stardate 53701.4 (September 13th, 2376), the Rhev travelled through an Iconian gateway, exiting together with dozens of other ships near the hazardous No Man's Land, which USS Voyager had been preparing to traverse. Rhev's alpha followed Captain Kathryn Janeway's invitation to Voyager, where their shared predicament was discussed among representatives of all displacees.
The alpha agreed to have Rhev join Voyager's caravan across the No Man's Land. The alpha and his beta met Janeway in her quarters on Voyager, and the Rhev's commander gave his word that the Hirogen would not prey upon the other fleet members. Nevertheless, the Rhev was among the ships not following Janeway's plan to cross a Mutara class nebula in an ordered fashion. Leader Sinimar Arkathi of the Todanian starship Relka took advantage of the fleet members' wariness of the Hirogen by framing them for the murder of the crew of Kuluuk vessel Eru. When the mass murder was discovered after crossing the nebula and Voyager published its findings, the Hirogen alpha and beta were put into protective custody in Voyager's brig to prevent the other displacees from attacking them.
When Arkathi's scheme was exposed, the Relka attacked both Rhev and Voyager before Relka's crew mutinied. Arkathi fled the ship in an escape pod, his fate unknown to the other caravan members. During the chaos, Rhev's alpha and beta briefly escaped from the brig but were captured and returned. Following the crisis, they promised to stay put. (VOY - Gateways novel: No Man's Land)
After Q offered Janeway to return the displaced ships, Rhev's alpha talked with Janeway for a final time and accepted the holotechnology offered by her. Once Q's fireball returned Rhev home, he joined his crew in torturing Arkathi, whom they had beamed from his escape pod. The alpha resolved to use the holotechnology not to stage virtual hunts but to set trap for flesh and blood prey. (VOY - Gateways short story: "In the Queue")