Professor David Pengelley presented "Sophie Germain's Grand Plan to Prove Fermat's Last Theorem" on May 11, 2020, via Zoom. Sponsored by the Oregon State University student chapter of the Association for Women in Mathematics (AWM), and introduced by Branwen Purdy, President of the AWM student chapter. The audience was primarily OSU Mathematics faculty and graduate students, and external guests Dora Musielak and Dominic Klyve. Abstract: The Oregon State University chapter of the Association for Women in Mathematics invites you to join in celebrating International Women in Mathematics Day with a special colloquium on a famous woman mathematician. Sophie Germain (1776-1831) is the first woman known to have created important new mathematical research. She is best known in number theory for the first general result aimed at proving Fermat's Last Theorem, finally proven only 25 years ago. However, her unpublished manuscripts, and a letter to Gauss, reveal that for her this result was only minor fallout from a multifaceted grand plan she pursued for proving the theorem outright, emphasizing new theoretical techniques of broad applicability. We will explore her grand plan and its side thrusts, including remarkable lower bounds on the size of possible solutions to Fermat's equation. Her work likely lay unread for nigh 200 years. We will also reveal a surprising connection between Germain's work and International Women in Mathematics Day, May 12. The presentation will be accessible to both undergraduate and graduate mathematics majors. This presentation will be similar to the 2014 Lonseth Lecture.