Stardate: 45959.1. Data's head is uncovered in an archaeological dig on Earth, where evidence is also found that aliens may have been on Earth as early as the 19th Century. Using modified technology, an away team follows Data into the late 1890s to investigate.

Stardate: 46001.3. The away team's investigations are hampered by a nosy Samuel Clemens. Picard discovers that he originally met Guinan in the 1890s on Earth.