Late at night KC and Marshall are sleeping out on the White House lawn when they see suspicious lights flickering at the top of the Washington Monument. If that's not strange enough, the next day a monkey is found inside the building.  KC and Marshall set off on a wild adventure to solve a 100-year-old mystery that involves a jewel thief, long-lost diamonds, and one of Washington's most famous and historic landmarks.


深夜在白宮草坪上露營的凱西和馬歇爾看到華盛頓紀念碑上閃爍著可疑的光芒。更奇怪的是，第二天他們在紀念碑內發現了一隻猴子。凱西和馬歇爾將開始一場刺激的冒險，一同解開這個牽扯了珠寶竊賊、失蹤的鑽石，以及華盛頓最有名歷史景點的百年謎團。