John Tanner, network news director, is looking forward to a weekend party with his closest friends – the Ostermans, the Tremaynes, and the Cardones. But then CIA tell him that they are all suspected Russian agents: fanatical killers working for Omega, a massive communist conspiracy. From this moment, Tanner and his family are caught up in a nightmare whirlpool of terror, helpless isolation, violence and slaughter. Until the shattering climax, Tanner cannot know who is a friend or who is an enemy….