Velvet Assassin is a stealth action game inspired by the life of Allied agent Violette Szabo. Dropped behind enemy lines in 1944, Szabo helped the French Resistance until she was captured and executed by the Nazis. In the game, the heroine is hospitalized and comatose. You play out her memories as she relives some of the things she has seen and done.
The emphasis here is on stealth. The heroine is invisible in the shadows or tall grass, from where she can strike with her knife. Close kills like this are the execution method of choice since they are silent and more effective than guns, which don't necessarily kill your targets unless you get them in the head. Sound is, so far, treated inconsistently. Walking on broken glass could clue in the Nazis to your presence, rattling a fence as you climb it will not, so long as you climb it in the shadows.