Vessel is the story of the passengers of Flight 298, a red-eye on its way from Boston to San Francisco. Midway through the flight the passengers encounter an otherworldly force and are subsequently thrown into a fight for their lives. The story focuses on Danny (an everyday traveler), Emma (a flight attendant), Chloe (an unattended underage passenger) and Jim and Murray (the two pilots).

Kate attends her estranged sister's bachelorette party at the request of their dying father. The weekend, held at a remote cabin booked on a home sharing app, turns into a savage life-or-death struggle that pits family against family, and past against present.