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Hagfishes possess flexible bodies that allow them to tie and manipulate body knots. These knots are used to remove mucous from the body, escape tight spaces, pull prey from burrows and, since they lack opposable jaws, to create leverage during feeding events. Despite its importance, knotting is poorly understood because this fast and three‐dimensionally complex behavior is difficult to study both in the laboratory and in their natural benthic habitats. To consistently stimulate analyzable knotting behaviors, we developed a novel restraint device to record high‐speed, biplanar video in three species of hagfish from two major taxa (Eptatretinae and Myxininae):Eptatretus stoutii,Eptatretus springeriandMyxine glutinosa. These data were analyzed to characterize knot type and kinematics of knot formation. We found that despite reduced radii of curvature and strain associated with more complex knots, all species of hagfish preferred the simplest overhand knots. While all species were physically capable of tying more complex knots,E. stoutiiexhibited a lower ‘behavioral’ stiffness by tying complex knots more frequently and coiling when at rest. The hyper‐flexible, hyper‐redundant hagfish body may require a high level of neural input for control. However, analyses of knotting motions indicate that hagfish seem to employ only four movements (body bends, twists, surface contacts and tail insertions into body loops) but in different combinations depending on the knot being tied. Furthermore, these movements and combinations are conserved across all species tested. We hypothesize that control of knotting in hagfish may employ motor primitives to reduce neural input.