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Then suddenly, as before under the eaves of the Emyn Muil, Sam saw these two rivals with other vision. A crouching shape, scarcely more than the shadow of a living thing, a creature now wholly ruined and defeated, yet filled with a hideous lust and rage; and before it stood stern, untouchable now by pity, a figure robed in white, but at its breast it held a wheel of fire. Out of the fire there spoke a commanding voice. "Begone, and trouble me no more! If you touch me ever again, you shall be cast yourself into the Fire of Doom." [ROTK: Mount Doom]
Smeagol touched the Precious and went into the Fires of Doom.