Abstract: A wire line operated shut-in tool for a tubing string of an oil or gas well has a locking mandrel for cooperation with a ported landing nipple disposed below a packer in the tubing string to lock the tool in position, and a mandrel core which passes through the locking mandrel and is axially movable relative thereto, the core having a lower portion which is surrounded by the locking mandrel and is caused to rotate by the engagement of pins projecting inwardly from the locking mandrel with a jay slot assembly machined on the outer surface of the core when the core is moved axially. The arrangement of the jay slot assembly is such that by operating the wire line to move the core axially relative to the locking mandrel, the tool can be cycled between respective positions in which the well can be flowed, the reservoir shut-in, or the tool run out of the well.