Whale Fall follows four estranged siblings connected only by their mother. Morgan is the oldest daughter from a pregnancy when Mom was in college. She was given up for adoption but had little contact and knew just the idea of her mother. Gwen is the next oldest, a step-daughter from a previous relationship, Mom helped raise her from five and left when she was six. She is the maternal one of the group who arranges the dinner, or should we say feast, for all the siblings to come together and remember Mom. Cordelia is the closest child to mom and adopted. Lastly we have Trent, the youngest child who is a product of an egg donation.  Mom was a marine biologist who studied whales and the ocean ecosystem. She was adventurous, fun and a free spirit. She has only been gone for a month. Gwen in her grieving, tracked down all the siblings and invited them to dinner at her home. Whale Fall is what happens at dinner when the siblings are finally together processing the death of their mom and her impact on their lives.