Ghost Town (2008)

After a near-death experience during a routine colonoscopy, people-hating dentist Bertrum Pincus is shocked to discover that he is suddenly able to talk to the dead. Constantly cornered by unhappy spirits who want him to help resolve their earthly problems, the misanthropic Pincus is driven to distraction. Eventually talked into helping the dearly departed Frank Herlihy, Pincus attempts to talk to Frank's widow, Gwen.