Well, as is often the case, there's good news and there's bad news.
The good news is that Novel #3 is basically finished and even has a title: The Fall of Moscow Station. Here's the blurb for it that recently ran in Publisher's Marketplace—
Mark Henshaw's THE FALL OF MOSCOW STATION, the third book in the Red Cell series, brings the trilogy to a head as CIA field agent Kyra Stryker and analyst Jonathan Burke chase a CIA traitor to an abandoned Soviet nuclear base outside Berlin, where they find themselves facing off against a Russian spymaster who's been selling advanced technologies to US enemies.
The bad news is that Simon & Schuster has decided not to publish it until May 2016...11 months from now. (Update -- official release date has been moved up to Feb 2! Huzzah!) It's quite a wait, I know, but unfortunately, I don't have any control over the publication schedule.
As a consolation prize, here's the nifty cover that S&S came up with for the mass market paperback of Cold Shot, due out later this year. The S&S graphic designers are working the Fall of Moscow Station cover art as we speak and I'll post it as soon as it's finished.