A gas spring and a retractable device cooperate to provide a two-way assist mechanism for controlling movement of a body panel. The retractable device includes a spring assembly received within a tube that is attached to the gas spring. The body panel is attached to a vehicle frame with a pivotal connection. One of the gas spring and retractable device is connected to the vehicle frame and the other of the gas spring and retractable device is connected to the body panel. The retractable device acts as a solid link as the body panel moves from a closed position towards an open position. Once a center of gravity of the body panel rotates beyond the pivotal connection, the retractable device resists further movement of the body panel until a fully open position is achieved.