Chase has a birthday coming up on the weekend, but he is in no mood to celebrate, because he has a 5,000 word research paper to write. In spite of that, the others are intent on throwing him a surprise party. Meanwhile, Dustin has gotten in trouble again, this time for swimming in the fountain, and Zoey is growing tired of bailing him out. She makes him promise to behave. Zoey also wants to give a thoughtful gift to Chase for his birthday. She later sees Chase preparing a birthday e-card for his grandmother, and learns that Chase and his grandmother have the same birthday, and that they have had a close relationship for a long time. Chase reminisces how his grandmother used to sing to him a song "A Million Raindrops" whenever he was down. Zoey later decides to, as a surprise to Chase, invite Chase's grandmother to the surprise party, and his grandmother accepts. She announces this to Logan and Michael who were deciding on a theme for the party. Although Logan and Michael had wanted to do a beach theme with swimsuits and girls in bikinis, that might not work out with Chase's grandmother in attendance, so they settle for a pajama-themed party.
Meanwhile Lola and wants to get a doodle cake from the vending machine, but the machine eats her money. Dustin volunteers to reach for it himself, but gets his arm stuck in the process, and no efforts of Lola and Quinn can get him unstuck. Lola and Quinn can't let Zoey know that Dustin's in trouble again, and they find themselves hiding him in the boy's dormitory machine and all. Later, while Chase still agonizes over finishing his paper, Zoey's surprise falls through when Chase's grandmother can't make the party because she has the flu, and she is disappointed. She still tries to make the most of it, by giving Chase a cupcake and a smaller present, and tells him that his grandmother was going to come over to visit , but had to back out because of her illness. Chase, being almost finished with his paper, agrees to attend his surprise pajama party (which he was tipped off about) and have fun on his birthday. Back in the dormitory, Dustin is still stuck in the machine, but upon buying himself a candy bar, manages to free himself.
Finally Zoey leaves the party to change into her pajamas, but when she returns, Chase has left, and the others assumed he wanted to finish his paper. Michael however privately informs Zoey the real reason Chase left: he got a call that his grandmother had died (her illness was more serious than the flu), and that Chase had quietly slipped out, not telling anyone but Michael what happened. As Zoey quickly leaves to find him, it starts raining. She finds Chase sitting in the rain, in a state of shock, and she sits with him, as he cries on her shoulder.