In Halloween II 1/2, as a Halloween party takes place in the Firehouse, two goblins sneak in unnoticed and release Samhain from the Containment Unit. The spirit of Halloween immediately sets up his headquarters in the Firehouse and captures the Junior Ghostbusters! 
The Junior Ghostbusters were trick or treating on Halloween night with Slimer. They stopped at a door and knocked. A woman answered with a bowl of candy ready. While she asked about their costumes, Slimer stuffed the bowl in his mouth. He then spit out an empty but slimed bowl. A tied up terrier barked at the Junior Ghostbusters and Slimer. The dog's bowl moved and a hand shoved it into the dog's face. It was one of Samhain's goblins. The terrier retreated into its doghouse but the second goblin rose up from beneath it. It then tossed the doghouse and dog away. The Junior Ghostbusters bumped into Samhain's two goblin minions and dropped their candy. Although the Junior Ghostbusters believed they are just kids in costumes, Slimer pondered about their real identity. Jason gave the goblins some candy as an apology, but they ran off into the night.
Slimer tailed the goblins and found out they dumped the candy into the bushes. Slimer presented the abandoned candy to the Junior's. It was decided they would follow the goblins even though Jason still wanted to trick or treat. The group ventured to the Ghostbuster's headquarters where they found the lights out and creepy faces looking at them. At first they were scared and backed away, until the lights went on and it turned out to only be the Ghostbusters and Janine in costumes. While everyone else started to party, Slimer danced with Janine but noticed the two goblins among the guests. They ran downstairs to the Containment Unit and locked the door from the inside. Slimer alerted the Junior's and they rushed downstairs. Slimer went in alone and saw the goblins messing with the grid. A burst of P.K.E. shot out of the Firehouse roof, prompting the party guests to leave. Egon, Peter, Ray and Winston went downstairs to investigate. However, they get down just after the goblins released Samhain from the Containment Unit.
Outraged that he was imprisoned, Samhain hurled an orb of P.K.E. into the wall. The energy caused the Firehouse to violently transform. The Ghostbusters retreated and hopped into Ecto-1 and narrowly escaped. The Firehouse then transformed into a ghostly fortress and Samhain placed up a protective shield that only ghostly beings could pass through, preventing the Ghostbusters from using light or Proton Streams against him. The more ghosts inside, the more powerful he and the shield became.
Outside the fortress, the Ghostbusters made a retreat as Samhain sent some ghosts after them. The Ghostbusters however managed to trap some of them using a Proton Cannon and Trap apparatus. Winston then created a smoke screen to brush off the rest. The Ghostbusters dropped the children off at their clubhouse. Back at the fortress, an angry Samhain decided to lead the rest of his minions to search for the Ghostbusters. The Junior Ghostbusters, now dressed in their jumpsuits, waited nervously for the Ghostbusters. A jerry rigged ghost detector started stirring all of a sudden. The Junior's headed outside and saw Samhain's army flying by and they decided to enter Samhain's empty fortress. They brought Ecto-Junior from the garage and headed out. Meanwhile, the Ghostbusters were finalizing their counteroffensive. Egon showed everyone the cosmic shape of the fortress and deduced all they had to do was change the shape and it would collapse.
The Junior Ghostbusters arrived at the fortress and encountered two of Samhain's minions. Donald managed to hold off the pair with a giant slingshot and pumpkin. However, they were soon captured by Samhain himself. Egon relented and announced he needed more data on the exact configuration of the fortress interior. Slimer was volunteered to acquire the intelligence. He was outfitted with a mini camera in his mouth so he could take it with him into the fortress. After he dodged various ghosts, Slimer discovered the captured children and Egon also saw a keystone. He explained it was the very spot where the Containment Unit used to be. He concluded that if it was destroyed, it would bring the entire fortress down. After they returned to the fortress, the Ghostbusters faced Samhain, who threatened to kill the children should they not surrender. After the Ghostbusters laid down their weapons, Slimer drew Samhain's forces while the Ghostbusters fired from a distance and hit them. Janine then activated the Proton Cannon and struck the keystone. Samhain is weakened by the damage done to the keystone and lack of ghosts to strengthen him.
Slimer was able to get the children out of the fortress using his own slime to allow them through the wall. The keystone then shattered and Samhain attempted to fight the Ghostbusters, but Janine used the lights on the Ecto-1 to stun him long enough for the fortress to crumble. Once the fortress crumbled, the Containment Unit (which was left open from Samhain's escape) was unveiled and Samhain was sucked back in. The Firehouse reappeared and the group continued their Halloween party.
|The Ghostbusters & Janine: HAPPY HALLOWEEN!|
|The Junior Ghostbusters: We're the Junior Ghostbusters, and we're not afraid of no ghost!|
|Samhain: Tonight, I shall bring about Halloween eternal.|
- It is the second episode to be based around Halloween
- The first being "When Halloween Was Forever"
- This episode features the return of Samhain, making it one of the few episodes to feature a villain as the main antagonist twice.
- A third Halloween based episode titled "The Halloween Door" premiered a few seasons later (though it did not feature Samhain).
- Class 5 Full Roaming Vapors are illustrated on page 23 of Tobin's Spirit Guide. 
- When Egon presents the team with a cosmic shape of Samhain's Fortress, there are several Japanese phrases in romaji are on the screen
- Yatashiwa Kugi Yo Urushiina
- Koredo Oshima!!
- Len Janson and Chuck Menville assigned Pamela Hickey and Dennys McCoy to write a Halloween episode.  Around the time, there were a lot of horror movie sequels thus "Halloween II 1/2" was written. 
- Due to network directives, this turned out to be the most conservatively written episode by Hickey and McCoy. 
- Hickey and McCoy simply wrote that Samhain would be sucked back into the Containment Unit at the end of the episode. Samhain's downfall was altered with Janine blinding him with light so that the Ghostbusters personally 'defeated' him. 
- On page 11 of Ghostbusters: Get Real Issue #3, the unused plastic flamingo prop appears by Winston.  
- On page 13 of Ghostbusters 101 #2, in panel 2, now on the monitor screens are:
- Top left: When the Junior Ghostbusters raise their club rings to the sky.
- Bottom left: When they're trick or treating, from candy giver's point of view, and Jason shrugs his shoulders.
- ↑ Eatock, James & Mangels, Andy (2008). The Real Ghostbusters Complete Collection booklet, p. 27. CPT Holdings, Inc.
- ↑ Jason (2009). The Real Ghostbusters - "Halloween II 1/2" (1987) (DVD ts. 01:42-01:48). Time Life Entertainment. Jason says: "We're Class Five Full Roaming Vapors, as illustrated on page 23 of Tobin's Spirit Guide."
- ↑ Pamela Hickey and Dennys McCoy (2009).The Real Ghostbusters- "Halloween II 1/2 " (1987) Visual Commentary (DVD ts. 01:51-02:09). Time Life Entertainment.
- ↑ Pamela Hickey and Dennys McCoy (2009).The Real Ghostbusters- "Halloween II 1/2 " (1987) Visual Commentary (DVD ts. 02:20-02:25). Time Life Entertainment.
- ↑ Pamela Hickey and Dennys McCoy (2009).The Real Ghostbusters- "Halloween II 1/2 " (1987) Visual Commentary (DVD ts. 11:12-13:00, 14:35-6:00, 21:52-22:04). Time Life Entertainment.
- ↑ Pamela Hickey and Dennys McCoy (2009).The Real Ghostbusters- "Halloween II 1/2 " (1987) Visual Commentary (DVD ts. 20:34-20:58). Time Life Entertainment.
- ↑ "Halloween II 1/2" Plastic Flamingo model sheet via Spook Central
- ↑ Dapperpomade Tweet 8/27/15
Episode Screen CapsEdit
Collages and EditsEdit
RGB DVD Boxset FeaturesEdit
|Previous Episode||Based on||Next Episode|
|Sticky Business||Air Date||Loathe Thy Neighbor|
|Sticky Business||DVD Order||Loathe Thy Neighbor|