Christina arrived at a New York bash dressed as a corpse bride - complete with pink wig, scars around her eyes and neck, a bouquet and bloodied wedding gown.
The 26-year-old singer's husband, Jordan Bratman, also vamped it up in a ghostly outfit.
'Mean Girls' actress Lindsay turned heads at a Hollywood bash wearing a black leather basque, stockings and suspenders. Dark locks and blood red lipstick completed her sexy look.
Other stars getting into the ghoulish spirit of the day included the Scissor Sisters. The flamboyant group donned spooky outfits as they played a special fancy dress show at London's Brixton Academy on Halloween (31.10.06).
Frontman Jake Shears dressed up as Frankenstein's monster, while Ana Matronic was his bride from beyond the grave.
Paris Hilton arrived for a Hollywood party dressed as a sexy version of comic book heroine Wonder Woman - wearing red suspenders, a blue mini skirt and a tiny blue halterneck top.
However, not everyone was impressed with her costume.
A source said: "Considering it was Halloween, her outfit made her look more like Blunder Woman. It wasn't scary at all - she was just flashing as much flesh as possible." In Los Angeles, pregnant model Heidi Klum and her husband Seal recreated the Garden of Eden scene - with Heidi dressed as the apple and Seal as Eve.
'Desperate Housewives' actress Eva Longoria also enjoyed dressing up - she arrived at the same party wearing a cat mask and a long black cape.