The Ross kids become concerned that history is repeating itself after a scary old doorman tells them a building legend about a nanny who did “something terrible” to the kids in her care on Halloween. Meanwhile, Jessie and Tony work together to crash an exclusive Halloween party so Jessie can give her short story to a famous magazine editor.

Jessie joins a comedy improv class and Tony goes to embarrassing lengths to prove his love for Jessie. Meanwhile, Ravi recruits Zuri to help him babysit Mrs. Kipling's baby lizards.

When Tony forgets their first anniversary, Jessie composes an angry ballad that goes viral. Luke tries to help build Ravi's self-esteem.

Emma gets upset when her friends gravitate to the new girl in school; Ravi helps Luke with a project about India.

Luke, Ravi, Zuri, and Stewart get locked in the penthouse panic room.

Jessie invites Bertram's mom out for his birthday. However, Bertram doesn't like his mom that much because she always steals the spotlight. Now, Jessie needs to bring the two together. Meanwhile, Ravi and Luke work on a science project together.

Future Jessie appears from a time machine to warn present Jessie that Ravi will cause a threat to her future life.

Jessie post a secret and Zuri reads it and thinks that Jessie is an alien, but Zuri tries to make Jessie to think that she's and alien too.

Tony and Jessie attempt to make each other jealous by asking their exes on a double-date, causing the duo to break their dating relationships, which also saddens Emma & Zuri in the process. Meanwhile, Luke & Ravi attempt to sabotage each others' plans on how to relieve Bertram's stress level. Unfortunately, this leads Bertram into thinking that the Ross brothers don't actually care about him. Also, he's hypnotized into thinking that he's a stray tomcat.

When Jessie's dad invites her out to the military camp to visit, Jessie and the kids embark on what should be a pleasant vacation, however when they arrive Jessie is shocked by some news her dad reveals. Not only that Jessie also meets her long time rival Darla again whose younger brother Caleb takes a shine to Emma. Emma and Caleb try to make their relationship work while Jessie and Darla do everything they can to try and break them apart.

Jessie and the kids are excluded from the building Halloween party. They throw their own party, which is interrupted when Emma and Luke become possessed by evil spirits.

Jessie's new agent gets her a job as a hand model.

Jessie decides that she and Tony will set each other up.

Luke asks his adoptive mom, Christina, for information about his family history after he is assigned a report at school.

When Teddy Duncan (Bridgit Mendler) gets accepted into a college in New York City, she goes to New York, alongside her brother P.J. (Jason Dolley), and meets up with Jessie. When a blizzard traps P.J and Teddy in New York City, Jessie and the Ross kids try to get them back to Denver the rest of the Duncan family go and get them as well. Meanwhile in Colorado, Gabe (Bradley Steven Perry) is being a scrooge.

Jessie and Zuri set out to host a birthday party for Taylor, a new friend who’s sorely missing her mother, a deployed member of the military. When Taylor decides she’d rather not celebrate anything without her mother, Zuri enlists the help of Mrs. Obama.

Jessie and Zuri discover Stewart has a new laid-back "manny" named Hudson. Having grown to like Stewart, Zuri resents being told not to see him, and they run off together.

Ravi's birthday present from his parents is a trip to outer space with the rest of the Ross kids and Jessie. Their trip takes an unexpected turn when Ravi ends up not going.

In the season four premiere, the Ross kids are convinced Jessie is headed to Africa to rekindle her relationship with ex-fiancé, Brooks. In an effort to stop her, the kids make the trip to Africa and quickly find themselves on a wild adventure.

Eager to play in Luke's basketball game, Ravi unexpectedly runs into LA Clippers star Chris Paul, who he enlists to coach him. Meanwhile, Jessie learns that Hudson is her new classmate and is unhappily forced to partner with him for an assignment.

When the kids are snowed in at the penthouse, an epic game of capture the flag ensues. Allegiances are tested, tricks are pulled and everyone goes a little overboard.

Emma wants her license, so Jessie teaches her how to drive. Ravi and Luke accidentally break one of Zuri's games, forcing a stand-off.

While on vacation, the Ross family finds a girl stranded in the middle of the ocean and invites her aboard their yacht. Meanwhile, Bertram stays home and babysits Mrs. Kipling, who has separation anxiety from Ravi.

While exploring an Italian island, the Ross family's tour guide tells a story about Jessie's necklace, and how its curse brings anyone who wears it bad luck in love.

In the final part of the "Rossed at Sea" three-parter, Jessie abruptly ends the Ross family vacation because the kids are constantly fighting. They wind up in a pickle when they find the yacht the next morning floating in the middle of the sea with no captain or crew in sight.

Bertram's new toupee that he bought for his band's big performance has gone missing, so Jessie interrogates each of the kids in hopes to find it.

While trick-or-treating, Stuart warns the Ross kids about a ghost named Abigail. Then, at a masquerade party, Jessie meets a mysterious, masked boy who she falls for.