Mrs. Williams is a minor character mentioned in File Under: 13 Suspicious Incidents, in the eighth incident, "Twelve or Thirteen."
Mrs. Williams was originally born as Miss Herman. She competed for years in the Ethan Frome Race.
She eventually married Mr. Williams, taking his surname, though the two of them still competed against each other in the Frome Race, including during the competition where the portrait of Gary Dorian was stolen. They continued to live in Stain'd-by-the-Sea after the economic collapse, working at the distillery.
- Her name, as well as the names of her fellow competitors, is a reference to "Willow Poem" by William Carlos Williams.