Plot summary
Nathan and William are stuck in the cave after a cave in. A boulder is blocking the way to the thinny, that is now closed up. William himself is stuck under a boulder. They see aether seeping in from a crack and William convinces Nathan to get him some. Meanwhile Hailie gets stuck in an iron gate, mortally wounded. Duke and Audrey are not able to convince her to open the thinny. Duke ends up releasing her from her suffering and using his trouble to absorb Hailie's trouble and open the thinny.
William uses the aether to conjure up a familiar minion to remove the boulder and when the thinny opens up he decides to let Nathan go. Nathan is safe and leaves William a parting gift, so he can return to his realm. Meanwhile, Vince, Dave and Dwight are trying hypnosis to let Dave fight Croatoan in his own mind. However, Maddie ends up dead and they learn Croatoan has been collecting the aether so he can emerge from Dave on his own. That time is coming very near. Dave realizes his weakness and takes away his mind-wiping ability, but is killed by Croatoan in the process. Then Croatoan escapes his mouth as a greenish cloud. Vince and Dwight find a message on Dave's arm he wrote on the notepad while fighting Croatoan which reads, "He's coming for Audrey".
Credits
Adapted from Wikipedia contributors, Haven season 5. HTML formatting and reference markers removed.