Halloween Scary Fun Action Plan is the third episode of Season 4 of Lloyd in Space, which was first broadcast on October 31, 2003.
Lloyd and the gang have a plan to scare Francine and her friends at Halloween, topping it off with Boomer's haunted house. But when Lloyd and the gang themselves go into the haunted house they are sent into the future, where all of Lloyd's friends turn into monsters, and he's left hiding on the station for the next fifty years. After admitting he misses Francine, and that he shouldn't have scared her, it turns out that it was a telepathic prank by Francine, with help from her friends and Boomer.
- Diedrich Bader as Boomer
- Clancy Brown as Officer Frank Horton
- Aria Curzon as Bitsy
- Eddie Deezen as Larry
- Bill Fagerbakke as Kurt
- Brian George as Station
- Pamela Hayden as Douglas McNoggin
- Nicolette Little as Francine Nebulon
- Tress MacNeille as Mrs. Bolt
- Courtland Mead as Lloyd Nebulon
- Justin Shenkarow as Eddie Horton
- Tara Strong as Nice Cindy
- April Winchell as Nora Nebulon