Macbeth encounters witches who foretell his kingship. Lady Macbeth hatches a plot to seize the throne. Guilt and paranoia consume them as rebellion and Lady Macbeth's spiral lead to their downfall, prophecies' sinister unraveling.
Macbeth encounters three weird sisters on his return from battle. They predict he will become King. He comes home and tells Lady M about the encounter and she's all let's make this happen honey. For those who would knock this being done in modern dress, Shakespeare was always done in modern dress. Probably why Shakespeare mentioned doublets in Julius Ceasar.