Nonexpression

• Asset at the card table
• Feature of some bluffs
• Card player's deadpan expression
• It's blank for a bluff
• Gambling asset
• Bluff concealer
• Inscrutable expression
• Expressionless visage
• Emotionless look

Wikipedia Word definitions in Wikipedia
Pokerface is a 1986 mini series about a former journalist who works as an undercover agent for Australia's secret service.