The falling action is when Princess Pea starts liking Despereaux. Princess Pea starts to talk to Despereaux but since she likes him she doesn't think its weird that she has conversation with a mouse. Other people in the castle think they are really weird and that is the reason Despereaux got captured. Despereaux's family didn't even care about him and people in the castle banned Princess Pea and Despereaux from even looking at each other.
The most important symbol is the needle and red thread. It is important because Hovis, the thread master gives Despereaux a sewing needle so he could use the needle as a sword. He got it so he could survive the dungeon and escape from it. Despereaux got a red thread tied around his neck since he got sent do the dungeon, later on in the story Hovis breaks the thread as a symbol of freeing him.
In the end, Despereaux and Princess Pea live happily ever after and Despereaux is allowed to be around Princess Pea whenever he wants. Since Princess Pea is very nice she allows Roscuro to walk anywhere he wants in the castle. Mig who is a servent girl in the castle also ends up happy in the end. Mig has her own happy ever after because she helped save Princess Pea from getting killed from Roscuro.