The snailfishes, family Liparidae (Scorpaeniformes), have found notable success in the hadal zone from depths ~6,000–8,200 m, comprising the dominant ichthyofauna in at least five trenches worldwide. The hadal fish community is distinct from the surrounding abyss where solitary, scavenging fishes such as rattails (Macrouridae), cutthroat eels (Synaphobranchidae), eelpouts (Zoarcidae), and cusk eels (Ophidiidae) are most common. Little is known about the biology of these deepest-living fishes, nor the factors that drive their success at hadal depths. Using recent collections from the Mariana Trench, Kermadec Trench, and neighboring abyssal plains, this talk addresses the role of trophic ecology, pressure adaptation, and life history in structuring fish communities at the abyssal-hadal boundary. These studies provide insight into the ecology and physiology of deep-dwelling fishes and inform new understanding of life in the trenches.