So, I just found 2 more tiny spoilers for the season finale.
First off, Lily Tomlin will be back to play Roberta, Mrs. McClusky’s (Kathryn Joosten) sister. Apparently Roberta and Mrs. McClusky will be working together to solve the mystery of Dave (Neal McDonough).
Speaking of Dave, it appears he’ll be taking Susan (Teri Hatcher) on a fishing trip…with plans of killing her. Hopefully Roberta and Mrs. McClusky will solve this mystery before Susan pays the price.