The Thirteenth Chair (1929)

Although his murdered friend was by all accounts a scoundrel a true "bounder" Edward Wales is determined to trap his killer by staging a seance using a famous medium. Many of the 13 seance participants had a reason and a means to kill, and one of them uses the cover of darkness to kill again. When someone close to the medium is suspected she turns detective, in the hope of uncovering the true murderer.