After having lost Ireena to Strahd in Barovia, the party was contacted by a mysterious voice from back in Faerun. He introduced himself as Zephyros, and told the party that there was a lot of trouble back home.
A short time later, Zephyros arrived and transported the characters in his flying castle to the town of Bryn Shander, way up north in Icewind Dale. He also advised them that he wasn’t sure how or why, but that it was very important that they speak to Sheriff Markham Southwell. After telling off a group of air cultists and talking down a Silver Dragon and group of Dwarves, the tower touches down just outside of Bryn Shander.