After barely escaping an explosion at Mason Industries, Wyatt (Matt Lanter) and Rufus (Malcolm Barrett) chase the Mothership back to a French battlefront during World War One to rescue Lucy (Abigail Spencer) from Rittenhouse. There, they discover that Lucy has recruited Marie Curie (guest star Kim Bubbs), the famous French scientist and the only person ever to win two Nobel Prizes, to help save the life of a wounded American soldier, only to learn that the soldier is Lucy's own great-grandfather who Rittenhouse is bringing to the present to be their leader.