Josie left the school and bumped into Kai after almost being killed.
We learned that Alaric sent a witch, a werewolf, and a vampire to the prison world 10 years before because they butchered a group of students.
Kai was playing Josie all along -- until she said that she had some of Bonnie's blood to get out.
He took it and Josie later escaped. In the end, however, it emerged that Kai was trying to escape.
His plan failed when we learned that Josie had cloaked a vodka bottle with blood to make him think he had everything.
Kai said he was killing himself in the Malivore pit, but he actually woke up in Mystic Falls with the Necromancer and Chad.
Lizzie tried to feel the romance with Sebastian, but she learned he wanted her to kill herself to become a vampire and end the merge.
She declined, siphoned the blood from him, dessicating him.
Josie later opened the mora miserium and activated her dark abilities, leading to Lizzie crashing the car with Sebastian and seemingly dying.
Did it really happen, though?