Cain/LeDuc started the 2017–2018 season with a fourth-place finish at the 2017 Lombardia Trophy in mid-September. They placed seventh at the 2017 Nebelhorn Trophy in late September. At their first Grand Prix event, the 2017 Cup of China, they placed sixth. They placed third at the 2018 US Figure Skating Championships. They placed second at the 2018 Four Continents Figure Skating Championships and earned their first medal at a senior ISU Championship.