With Halloween fast approaching, Cassie and the town of Middleton are hard at work preparing for the annual Harvest Festival. This year, Cassie is transforming Grey House into a delightful haunted house, and when a handsome stranger checks in, the family suddenly find themselves on edge.

The author of a series of magic-and-romance-filled novels comes to Grey House to celebrate the release of her newest book, titled "The Enchantress Unites." But it's Cassie who ends up doing the uniting, bringing together the people of Middleton to put on the special event while also coming to a special realization about Sam.

A long-forgotten prophecy is unearthed and when the things that were predicted to happen start to come true, the people of Middleton begin to fear this might be the sign of a horrible curse.

Cassie and Sam puts their energy into the bicentennial Halloween Harvest Festival. Everyone in town prepares for the festival’s competition with rival town Blairsville. When a 100-carat ruby known as The Heart of Middleton is stolen from the museum where the festival’s gala is to be held, Cassie suspects a Grey House guest is the culprit.

The Good Witch meets her match when Cassie's long-lost college roommate, Autumn Delaney, makes an unexpected visit to Grey House on a mission to disrupt Middleton's Halloween festivities.

Now empty-nesters, Cassie and Sam celebrate their first wedding anniversary. Abigail and Donovan’s relationship continues to be challenged by their families’ curse. Cassie’s Grey House guest has intentions for visiting Middleton that are different than she claims.

Cassie judges Middleton’s chili cook-off, which brings out fierce competition among residents, including Sam. Martha receives unexpected competition in her once-uncontested run for re-election. Cassie unearths a time capsule that reveals information about her current Grey House guest’s background.

Cassie, Abigail and Joy browse an estate sale, where Joy hopes to find a clock for Martha's renovation. Stephanie's ex-husband, Wes, comes to town to pack up their shared cabin.

Martha fills in as the local Dear Debbie advice columnist, getting an anonymous letter that adds intrigue to a progressive dinner attended by all of the Middleton couples.

Cassie pursues a temporary art history professorship while Sam diagnoses Adam. Abigail and Donovan realize that the missing diamond from the Middleton treasure may help break the curse.

Cassie gives her art history students a lesson on perspective. Sam performs surgery on Adam, who worries about his recovery. Joy’s troubling dream about Abigail and Donovan may not be what it seems. Martha courts a French delegation to secure Middleton’s status as its sister city.

As Cassie gets ready for Grey House’s 225th birthday Martha leads the group in a tableau vivant recreating a Nathaniel Merriwick painting, leading to new clues surrounding the Merriwick-Davenport curse. Joy experiences life differently when her intuition suddenly takes a holiday.

Cassie welcomes a chocolate festival to Grey House where the confection has a special, sweet effect. Sam and Donovan discover a new clue surrounding the Merriwick-Davenport curse, while now-single Abigail gets an unexpected visit from a college friend for a surprising reason.

When Cassie and Sam’s weekend in Chicago gets canceled because Sam has to stay behind for work, she and her book club friends hit the road instead. While the ladies recharge the weekend also comes with surprises, including a potential clue about the Merriwick-Davenport curse.

Cassie’s teaching position winds down and Sam is forced to take vacation time so they try out different hobbies together. Joy’s faced with a decision when Donna accepts a job for them in Vermont. Abigail and Donovan make one last stand against the curse.