A tie-back string and a method of coupling the tie-back string to a casing is disclosed. The tie-back string is disposed within the casing. The tie-back string includes an anchor and an actuator section. The actuator section including a sleeve that forms a first chamber and a setting piston that forms a second chamber. A pressure differential is created between the first chamber and the second chamber to move the setting piston to engage the anchor of the tie-back string.