"Have a shot of tequila first, cheer up!" Shahriyar tells guests gathered at his luxury apartment in Tehran. His girlfriend, Shima, says they party every weekend.

"Shahriyar has one rule: Bring your booze! We drink until morning," she said on a Facetime call as lights flashed to rap music in the background.

Despite the ban on alcohol and frequent police raids, drinking in Iran is widespread, especially among the wealthy. Because the Shiite-dominated Muslim state has no discos or nightclubs, it all takes place at home, behind closed doors.