A method and apparatus for conducting a reverse flow operation. The apparatus may be lowered into a wellbore on a work string, and includes an opening device, a closing device, and a locking device disposed in a housing. Pressurized fluid supplied through the work string may actuate the opening device to open fluid flow through ports in the housing. Pressurized fluid from the annulus may be supplied through the port in the reverse flow direction to actuate the locking device to enable fluid flow up through the work string back to the surface, and to release the closing device. Pressurized fluid supplied through the work string may actuate the closing device to close fluid flow through the ports in the housing.