Working in the mountain quarries, narrow-gauge engine Rusty knows that to stay safe you've got to see trouble before it gets to you, so he keeps his eyes open for danger. Those boulders sitting up high on the ridge can come down fast and Rusty doesn't want to be there when one does! This mountain tunnel wooden railway accessory includes the scenic Blue Mountain, the engine, and a gigantic boulder which looks mighty scary to little Rusty. Do you think it's safer to go fast or to creep slowly by the monster poised above? Tell Rusty, he's scared to do either!