I think Lady Macbeth wasn't involved at all because Macbeth does not tell her. Also, Macbeth does not want to keep her worried. So Macbeth says "Be innocent of the knowledge, dearest chuck, / Till thou applaud the deed.". This means that Macbeth is telling Lady Macbeth to digest the deed about Duncan first. This is what i remember its been a while since i read the book. But hope this helps.
