Rumble is feeling grumpy. He always is, especially in winter. He hates winter. It's nothing but a reminder of the family he lost, and the night he nearly died. So, when the Doctor takes him back to Hearth's Warming Eve in Old Trottingham, the pegasus is less than happy. Things only get worse when the duo are dragged into a web of murder and intrigue at the Frost Faire. Aided only by a carnival worker and attacked by undead monsters, this may be the last Hearth's Warming for the entire world.