An aquatic amusement toy including a buoyant body and an underwater member. The buoyant has a housing including an engaging portion, a first protruding shell and a second protruding shell, and the underwater member has a first and second face and a receiving portion communicating through the first and second surface. The engaging portion of the buoyant body is engageable with the receiving portion of the underwater member. In use the buoyant body is coupled with the underwater member and sinks in water such that the first protruding shell or the second protruding shell keeps the buoyant body at a predetermined height above the bottom of water, and when the underwater member is depressed to disengage from the buoyant body, said buoyant body floats to the surface of the water and the underwater member remains immersed.