From the Houdini Estate to Marilyn Monroe's Brentwood hacienda, these are the celebrity haunted houses that built Hollywood's ghost-story economy.

Inside celebrity haunted houses, sheet-covered furniture allegedly rearranges itself overnight. Lucille Ball's Roxbury home has decades of consistent reports.

The defining feature of celebrity haunted houses is the long Spanish-style hallway. Voices, footsteps, women's names called out — the architecture amplifies it all.

In celebrity haunted houses, antique brass keys reportedly turn on their own. The Houdini Estate is famous for this — the master himself was an escape artist.

In multiple celebrity haunted houses, antique pianos reportedly play overnight without anyone present. Errol Flynn's Mulholland House was the original.