Radiant Angel

"A soft breeze fluttered the white, blue, and red Russian flag in front of the U.N. mission. I remember when the Soviet hammer and sickle flew there. I kind of miss the Cold War. But I think it's back."
A QUIET END
After a showdown with the notorious Yemeni terrorist known as The Panther, John Corey has left the Anti-Terrorist Task Force and returned home to New York City, taking a job with the Diplomatic Surveillance Group. Although Corey's new assignment with the DSG-surveilling Russian diplomats working at the U.N. Mission-is thought to be "a quiet end," he is more than happy to be out from under the thumb of the FBI and free from the bureaucracy of office life.
But Corey realizes something the U.S. government doesn't: The all-too-real threat of a newly resurgent Russia.
When Vasily Petrov, a colonel in the Russian Foreign Intelligence Service posing as a diplomat with the Russian U.N. Mission, mysteriously disappears from a Russian oligarch's party...