Spoiler alert: here is the first part of the plot, as summarized by Wikipedia…
It’s Anna’s birthday and Elsa plans to throw her the perfect surprise party with the help of Kristoff, Sven, and Olaf. However, after planning the huge party and as Anna is being led on a “party treasure hunt,” by following a string that winds through the kingdom, Elsa finds that she has caught a cold. She starts sneezing and produces a group of small snowmen much like Olaf, with each sneeze—
ME: (Stops. Blinks)
ME: Elsa! Olaf! What did you do?!