Reign of assassins

映画「レイン・オブ・アサシン」について: 「レッドクリフ」のジョン・ウーが、アジアのトップスターたちを豪華に起用. Get an answer for 'What does the following quote mean in Macbeth? I am in blood/Stepp'd in so far that, should I wade no more,/Returning were as tedious