Shadow Hours (2000)

Michael Halloway wants to start a new life with his pregnant wife Chloe and put behind him a past filled with drugs and alcohol. Working as a night gas station clerk in Los Angeles trying to make an honest living, he's befriended by the elegant and mysterious Stuart Chapell who entices him to join in his "research" for an upcoming novel. What starts as a fairly innocent journey into the seedier side of the city's nightclubs turns into a swift descent into sinful pleasure, decay and debauchery, forcing Michael to make certain choices; choices that will determine who will win his soul.