On 6 June 2005, the ROV Tiburon of the Monterey Bay Aquarium Research Institute captured approximately 24.4 min of footage (30 frames s⁻¹) of a female ceratioid anglerfish, identified as a member of the genus Oneirodes, off the coast of Monterey, CA, at a depth of 1474 m. To gain insight into ceratioid behavioral ecology, this sequence was digitized and analyzed frame-by-frame. All relevant behaviors were described and the kinematics of one slow-swimming and one directional change sequence were quantified. These sequences captured both reduced (slow-swimming) and prominent (directional change) functions of the pectoral fins in producing motion. The angler was initially sighted passively drifting with its illicium extended. It swam away rapidly when approached by the ROV, but for most of the time, it remained lethargic, drifting with no preferred body orientation. When progressing, however, the fish swam slowly and intermittently at approximately 0.24 body lengths s⁻¹, with its pectoral fins beating in-phase. Overall, the observed behaviors of Oneirodes support the hypothesis that these animals are lethargic, lie-and-wait predators, well adapted to the low energy conditions of deep-sea environments.