Jessie accepts a job as a nanny and moves in with the Ross family, high-flying couple Christina, a former supermodel turned business mogul, and Morgan, a famous movie director, their four kids Emma, Ravi, Luke and Zuri and their beloved 7-foot Asian Water Monitor Lizard. Nanny responsibilities are more difficult than Jessie anticipated as she coaches Emma, who is on the brink of a science fair meltdown.

Jessie and Bertram are left in charge of bringing the Christmas spirit to Ravi, Emma, Luke, and Zuri. Lukes wants to kiss Jessie under the mistletoe. At the toy store, Jessie, Emma & Luke get caught in Toy Jail. But when their parents are stranded because of a blizzard, things go wrong. Zuri tells Ravi about Santa and Ravi gets petrified by him. The parents make it home for Christmas and Luke quickly kisses Jessie.

A celebrity comes to the Ross household. Emma and Jessie fight for his affection,while Zuri and Luke make prank phone calls. The star asks Jessie out but Emma ruins it. Bertram pretends to work while Mr.Ross is in town.

While the Ross Family has their traditional "Gotcha Day", Jessie is left in charge to help celebrate the time when Zuri was first welcomed home in New York City. When Ravi tells the story when he first arrived in the United States, he tells Jessie that they thought Mr. Kipling was supposed to be a baby because his room was decorated as a nursery. Jessie accidently blurts out that Morgan and Christina were probably expecting a baby. Ravi gets incredibly upset; Christina gets infuriated with Jessie. The huge reveal almost ruins "Gotcha Day". Later on, Morgan and Christina tells them that his birth certificate had a typo and instead of Ravi being born in the year 2001, it said 2011, so that is why the Ross' were expecting a baby. In the end, Ravi forgives Morgan and Christina, and they give Zuri a zebra as a "Gotcha Day" present.