Oh no! An ancient mummy is haunting the Fermentation Lab, munching on umami-filled ingredients like stinky cheese. This gives John Henson the idea for "umummy" desserts, and he tasks the bakers with creating sweet mummy treats that feature umami ingredients like red miso, aged parmesan, gochujang or soy sauce. Then, it's "bone appetit" for judges Carla Hall, Zac Young and Stephanie Boswell as the bakers get inspired by the lab skeleton, Skelly, to create Skelly's forgotten desserts, where they must use Halloween mini chocolate bars to create skeletal desserts.

The final bakers take on two very difficult challenges inspired by the past -- all leading up to a time-traveling monster mash! In the Dissection Lab, John Henson works on some gross anatomy, and he asks the bakers to create desserts with gummy hearts that will be "dissected" by judges Carla Hall, Zac Young and Stephanie Boswell. Then in the Quantum Physics Lab, John hops into a time machine and journeys to the ancient past for inspirations like medieval vampires and early aliens for time travel cakes. The best baker heads into the future with the Halloween Baking Championship title and the $25,000 prize!

John Henson has a problem in the haunted Paranormal Research Lab, and he's hoping to summon the spirit of Beetlejuice to help broker a deal with the other spirits. To butter up the ghost with the most, John asks the bakers to make black and white desserts using black and white ingredients. Then, John challenges the bakers to create Shrinker desserts that feature a tiny desert on top and large dessert on the bottom. In the end, judges Carla Hall, Zac Young and Stephanie Boswell banish one baker to the cyro-chamber.

John Henson catches a spirit doing some imaging in the X-ray room! The films the spirits have been taking of themselves are monstrous, and John wants the bakers to use these X-rays as templates for build-a-spirit desserts. Then, the bakers enter the lab basement where the portal to the underworld is kept locked behind a secure heavy door, but lately ghouls have been letting all sorts of otherworldly creatures out! The bakers make a portal entremet that reveals an otherworldly creature to judges Carla Hall, Zac Young and Stephanie Boswell.

As John Henson lays a dead flower to commemorate the lost souls at Henson & Sons Carnival, he asks the finalists to make flourless desserts. Then, the bakers create cakescapes depicting new carnival attractions for the grand re-opening, where judges Carla Hall, Stephanie Boswell and Zac Young will name the Halloween Baking Champion!

Five bakers remain, and the creepy, dangerous donuts they whip up in the first challenge are a sight to be seen. Then, for the main challenge, the bakers dig even deeper into their baking skills with graveyard pumpkin desserts that are to die for. But one baker won't make it out alive.

The final four bakers take on a haunted house cake battle for the title of Halloween Baking Champion and the $50,000 grand prize!

Ten bakers explore the Chemistry Laboratory at Henson Labs, where the safety rating is negative 35. Lately, the spirits who haunt the lab have been demolishing all the beakers and petri dishes, so host John Henson leans into this devastation and tasks the bakers with creating broken glass desserts that feature sugar glass. Then, there's been a horrible spill in the Chem Lab, so John has a little fun with it and asks the bakers to create sinister bubbling desserts inspired by the toxic mess. Judges Carla Hall, Zac Young and Stephanie Boswell test their poison tolerance before sending one baker to the cryo-freeze.

Down to six bakers and it's time for a big, bad, monster mash. The bakers spook the judges with their sculpted scary treats and then mash up flavors and themes to create devilishly delicious desserts! But one baker's creepy concoction doesn't cut it and gets the axe.

Nothing says Halloween more than scary monsters, and in the pre-heat, the seven bakers must create creepy bite-sized monster treats. For the main heat, zombies attack as the bakers are faced with whipping up a zombie dessert that makes the judges hungry for a bite.

Five talented bakers have survived the Camp Devil's Food Lake killer, and host John Henson challenges them to make patterned roll cakes and frightening fault line cakes. The competitors will have to kill the cake game to get past judges Stephanie Boswell, Carla Hall and Zac Young.

Host John Henson welcomes a dozen bakers to the Henson & Sons Carnival, where they're ready for the ride of their lives. First, they must layer a "tarot-misu" depicting the carnival's untimely demise. Then, the bakers scare up a new carnival mascot by designing creepy clown cakes for judges Carla Hall, Stephanie Boswell and Zac Young.

The bakers make desserts designed to melt after hearing John Henson's torrid tale of one of the carnival's most enthralling sideshow attractions, the Human Ice Pop! Then, a miscommunication spells the end for the sword swallower as the bakers create a dessert that swallowed another dessert to impress judges Carla Hall, Stephanie Boswell and Zac Young.

John Henson challenges the remaining bakers to create torta della nonnas that honor the matriarch of the Henson & Sons Carnival, the Tattooed Woman. Then, a mysterious swap smashes the Strong Man, which inspires the bakers to smash their desserts in front of judges Carla Hall, Stephanie Boswell and Zac Young.

The bakers dig deep to make buried alive trifles honoring the carnival's escape artist who went to an early grave. Then, John Henson shows the bakers the carnival's wind chimes, which look eerily like some of the missing family members' heads, and asks them to make shrunken head pies for judges Carla Hall, Stephanie Boswell and Zac Young.

Five remaining bakers take a light, sweet and utterly harmless dessert and head to the dark side; it's a main heat filled with frights as the bakers make scary mask desserts to spook the judges; one baker is eliminated at the end of the round.

Descending into a spooky cellar is enough to make any baker's blood run cold, and blood is always on the menu for a vampire party. Host Carla Hall asks the eight remaining bakers to team up and create desserts for a vampire buffet to satisfy the bloodsuckers' appetites as well as Carla and the other judges, Stephanie Boswell and Zac Young.

In the devil's den, host Carla Hall challenges the six remaining bakers to conjure up a devilish dessert using unusual ingredients, such as sauerkraut, beets, tamarind paste and canned tomato soup. The competitors must get creative to avoid the fiery pit of elimination and impress Carla and the other judges, Stephanie Boswell and Zac Young.

Host Carla Hall invites the five remaining bakers to a party in the haunted ballroom. For a spot in the finale, the competitors must create impressive costume cakes that will dazzle Carla and the other judges, Stephanie Boswell and Zac Young.

Do-nut try to steal John Henson's dream job, or things might get bloody. The remaining bakers make bloody filled doughnuts to commemorate an unfortunate accident. Then it's a joyful bake for some and doomed one for others as the competitors take judges Carla Hall, Stephanie Boswell and Zac Young round and round on the creepiest carousel ever.

John Henson tells the story of the ghost in the funhouse hall of mirrors as inspiration for the bakers' Bloody Mary bar desserts. Then, the magician known as the Fantastic Fondante puts on a show as the bakers work in teams to fuse two body parts together as Franken-cakes for judges Carla Hall, Stephanie Boswell and Zac Young.

As their nightmare begins in the grand foyer, host Carla Hall encourages the 10 competitors to reveal their deepest fears by baking haunted house cakes. Then, the bakers compete in the dagger game for a reward that could be the difference between life and death in the competition judged by Carla, Stephanie Boswell and Zac Young.

The seven remaining bakers continue their journey through the haunted house to the creepy nursery. Host Carla Hall challenges the competitors to bake 3-D demon doll cakes with a diabolically assigned flavor to be judged by Carla, Stephanie Boswell and Zac Young.

It's prom night at Camp Devil's Food Lake, and host John Henson puts the six remaining bakers in charge of the party snacks. As they learn more about the serial killer, a tsunami of terror will claim one more victim from the competition with help from judges Stephanie Boswell, Carla Hall and Zac Young.

Host Carla Hall meets the nine remaining competitors on the frightening front porch, haunted by eternally disappointed trick or treaters. The bakers are challenged to create Halloween candy croquembouche with a stunningly sweet illusion to impress Carla and the other judges, Stephanie Boswell and Zac Young.