Sentence:  These include a brief but showstopping (and trailer-revealed) scene where Vanellope crashes a Disney Princess reunion, packed with gags and references that should send both young and old fans into paroxysms of glee. The princess confab also leads into a scene featuring Vanellope and the cast of Slaughter Race that probably shouldn't be <WSD>spoiled</WSD>. 
Meaning of the word marked with <WSD> tags:  To reveal the ending or major events of (a story etc.); to ruin (a surprise) by exposing it ahead of time.