The first scene was a musical dream sequence, which turned out to be Serena's dream. Serena as Marilyn Monroe was singing 'Diamonds are a girl's best friend' and enjoying the attention she got from all the males of the cast. That was the case at least in the beginning, because when Blair emerged as Audrey Hepburn, she encharmed Dan. Despite Serena's attempts to keep him from going with Blair, Dan chose Blair instead of her. And that dream was basically her subconscious showing her that even though she denies it Dan is in love with Blair.
When Serena wakes up, she faces an overly excited Dorota. I actually think I missed Blair and Dorota's interaction during the wedding. Dorota is very important to her, just like a mother as she practically raised. I thought that at such an important day, there should have been a cute scene with her and Blair or even one encouraging her to stop the wedding.Dorota reminds Serena that she has to attend Blair and Louis breakfast buffet.
Dan has a short conversation with Rufus that actually reveals us that Dan isn't yet aware that his and Serena fake relationship could have easily ended in the last episode, as it wasn't necessary any more. Furthermore, Dan declares that he has no intention to ruin Blair's wedding but he knows someone who might (implying Chuck).
Chuck actually surprises me positively this time as his whole alliance with Father Cavalia was actually just to protect Blair. I have to admit that I was unfair with Chuck in the previous episode. It seems that he is still as mature as he was before the accident and he truthfully wants Blair to be happy. I would be actually really annoyed if he chose to humiliate her like that.
Chuck poisoned Father Cavalia so that he would feel ill for the rest of the day and unable to conspire against Blair. Fortunately for Father Cavalia, Georgina shows up, eager to stop the marriage herself.
And when Serena finally goes downstairs to attend the breakfast buffet, the first parallel to the pilot is apparent. She is standing on the top of the stairs and at the same time Dan walks in and reluctantly smiles at her. She smiles back.
Actually, this scene is full of parallels as when Serena needs someone to dance with her after the wedding, Dan offers to help her. (Just like when Serena needed to a convincing reason to not attend the kiss on the lips party, because Lily insisted on her going there, Serena and Dan said that they wanted to go to a concert.)
The last parallel from this scene comes when Blair finally walks in, interupting Dan and Serina's talk, while in the pilot she interupted Serena and Nate's first meeting by closing the door leaving Nate behind it.
Blair asks for Serena and tells her just how excited she is that she is getting married and becoming a princess. She also confesses that she is afraid that something would happen that would ruin the wedding and Serena quickly reassures her that everything will go as planned.
Meanwhile, Nate meets the real Charlie. Is this way too soon to say that I would love them as a couple? Probably it is, but we already know that they both have some problems with their parents and at this stage of their life, they both try to ensure their indepence from their families. Charlie obviously lied to him, when she introduced herself as Lola, but it would be easy for her to understand that Nate is in someway related to the Rhodes family, so it's perfectly clear why she lied. And most importantly, I think that Nate has grown a lot during Season 5, so he is ready for a new relationship.
Blair encouraging Serena to tell her feelings to Dan when they were getting ready for the wedding is basically everything a Derena shipper could ask. Blair initially thought that Dan and Serena got back together, but after Serena denied this, Blair figured out that Serena hadn't told Dan that they could stop fake-dating. Then, Blair starts explaining her how her act shows that she is in love with him and that she is afraid, just like she was a year ago when she pretended that there was a choice to be made between Dan and Nate. ( That must have felt like a punch to both Serenate and Dair fans.)
And this conversation was what made me forgive Serena for taking so long to choose between Dan and Nate. I was holding this against her for some reason, because Dan immediately knew that he wanted Serena. In my opinion, this situation with Nate and the following with Ben were the reasons Dan probably got tired of waiting for Serena and fell so hard for Blair. Back then, Blair basically told him that his whole life was revolving around Serena and that he was neglecting his writing and his own life. As soon as Dan realised that and Serena's reluctance to commit, he decided he had to move on.
Eleanor and Dorota come in the room, when Blair's suffering from severe anxiety... This makes Eleanor realise that this wedding doesn't make her daughter happy.
Nate and Dan want to ensure that Chuck (who is the most honest person Nate knows!) won't try to stop the wedding. Chuck quickly refuses that he has the intention to do it and actually thinks Dan is most likely to try. However, Eleanor's sudden arrival changes Chuck's plans for the day, as she convinces him to go stop the wedding.
To be continued...