The Ewing family learns of Mark Graison's death. Bobby and Jenna hold off their announcement. Jenna fears that Mark's death may bring Bobby and Pam together. Pam gets a letter from Mark which reveals the real cause of the plane crash. A phone call from Dusty raises the tensions between Clayton and Jessica. Clayton tells Ray and Donna the truth about Dusty and Jessica's diary. Pam and Bobby talk about their years together and the divorce. Pam learns about the letter which Katherine wrote and which led to Pam and Bobby's divorce. Pam has a showdown with Katherine. Miss Ellie and Jessica disappear and the Ewings fear Ellie is in serious trouble.