Abstract: In one specific form, the apparatus is embodied as a tubular housing which fits in the hand of the user, with a trigger-like release arm protruding from a slot in the side of the housing to be pulled rearwardly by a finger of the user. The release arm retracts a spring-loaded plunger within the tubular housing so that the plunger head clears a slot extending midway into the housing from one side, such that a weighted downrigger cable or line may be readily slipped into the slot and the arm released to allow the plunger head to seat against that portion of the downrigger line within the slot in the tubular housing, thereby capturing and entrapping the downrigger line securely within the slot by a two-point engagement which securely holds the device in place without permitting it to slide along the line.