I caught one episode of [link|http://www.amazon.com/Sleepers-Nigel-Havers/dp/B000L2127W/ref=pd_bbs_sr_2/002-2489031-3680034?ie=UTF8&s=dvd&qid=1176670602&sr=1-2|this] about fifteen years ago when it was broadcast stateside under the PBS "Masterpiece Theatre" imprimatur. The premise relies on what the producers did not realize was a historical sliver of time: in the reformed glasnost USSR it is belatedly discovered that two KGB "sleeper" agents inserted into the United Kingdom in 1965 are unaccounted for in 1991, their handler having been purged back in the day. A fanatical "Ninotchka"-like KGB major takes it upon herself to track down the missing moles, each of whom turns out to be quite comfortably ensconced in his respective (and widely separated) class tier, and reluctant to return to the rodina. Probably not a keeper, but once it shows up on Netflix likely worth four hours of your attention as a kind of coda to Cold War narratives.
cordially,