No one was unhappy when World War II ended, but the demise ofFoyle’s Waris something else entirely. For fans of this first-rate British murder mystery series, set against the backdrop of that epic conflict, Set 5 represents something of a reprieve; although Detective Chief Superintendent Christopher Foyle (Michael Kitchen) retired at the end of Set 4, circumstances force him to return to action in "Plan of Attack," the first of three 90-minute episodes (each on its own disc) offered here. But by the end of this set, the war is over and Foyle has eased back into retirement. That’s lamentable. Smartly conceived and often quite masterfully executed, this show will certainly be missed.  "History meets mystery" has been the concept from the beginning, as the low-key (like Peter Falk’s Columbo, he knows much more than he lets on), unfailingly decent Foyle and his assistants, Sgt. Paul Milner (Anthony Howell) and driver Samantha "Sam" Stewart (Honeysuckle Weeks), solve murders and various other crimes in and around bucolic Hastings, England, while WWII rages on at home and abroad. But this time out, the war provides much more than context, as the murders tend to be directly related to it. What’s more, Set 5 affectingly deals with combat’s heavy emotional psychological toll. It’s a burden we see carried by the cartographer who can’t bear knowing that his work is helping to kill innocent German civilians (in "Plan of Attack"); by the maimed former POW struggling to readjust to life at home, the teenager whose job it is to deliver bad news telegrams to soldiers’ families, and the Jewish doctor, a refugee from Poland, whose survivor’s guilt leads him down a very dark path (all three in "Broken Souls"); and even by Foyle’s own son (Julian Ovenden, in "All Clear"). OK, so the mysteries may not be all that mysterious--perceptive viewers will have little difficulty identifying the culprits. But with its multi-layered storytelling (the scripts were written by creator Anthony Horowitz) and fine production values (the cinematography, editing, and music are all excellent),Foyle’s Waris a whodunit that’s both a prime example of its genre and thoroughly successful on its own unique terms. Bonus features include a brief "making of" featurette and cast filmographies.--Sam Graham