The Land That Time Forgot is a fantasy novel by American writer Edgar Rice Burroughs, the first of his Caspak trilogy. His working title for the story was "The Lost U-Boat." The sequence was first published in Blue Book Magazine as a three-part serial in the issues for September, October and November 1918. The complete trilogy was later combined for publication in book form under the title of the first part by A. C. McClurg in June 1924. Beginning with the Ace Books editions of the 1960s, the three segments have usually been issued as separate short novels.

バローズが描く孤島キャスパックの魅力は、生命の進化を凝縮した独創的システムにあります。大戦の文明から原始の弱肉強食へと堕ちるサスペンスは、読者の生存本能を刺激します。個体が段階的に進化を遂げる設定は、空想科学への深い洞察と冒険ロマンが融合した文学的白眉といえるでしょう。 映像版が巨大生物の迫力を視覚化する一方、原作は未知への恐怖と極限下の葛藤を克明に刻みます。実写の躍動感とテキストが紡ぐ内省的な深みが共鳴する時、この悪夢的で美しい楽園は、より重層的な奥行きを持って読み手の魂を激しく揺さぶるのです。