A rope-guide device suitable for marine use as a crab-pot puller, an anchor puller, a shrimp-pot hauler, and the like includes an arcuate, side-entry slot running the entire vertical length of its cylindrical body. A unique lock-mechanism prevents rope slippage by crimping the rope between the interior wall of the body and a tongue-like locking mechanism with a positive-tension device. An optional handle, which protrudes exterior of the body and extends interior the body, resting against the locking mechanism, assists release by a user-activated motion on the handle.