In both scenes, Lady Macbeth is portrayed as a nefarious, malevolent woman who is extremely ambitious and willing to become queen at all costs. She is depicted as a cruel, malicious individual who cunningly plans King Duncan's assassination and persuades her husband to follow through with the crime. Lady Macbeth shows no signs of remorse or sympathy in either scene and is portrayed as more of an ambitious, daring person than her husband.
In act 1, scene 5, Lady Macbeth reads her husband's letter regarding the witches' prophecy and reveals her ambitious, malevolent nature during her soliloquy. In Lady Macbeth's soliloquy, she urges wicked spirits to fill her with cruelty and make her callous, murderous, and evil. Lady Macbeth says,
Come, thick night, And pall thee in the dunnest smoke of hell, That my keen knife see not the wound it makes, Nor heaven peep through the blanket of the dark To cry “Hold, hold!" (Shakespeare, 1.5.40-44).
After asking for a cold, unforgiving, murderous heart, she instructs Macbeth to act friendly to the king while she takes care of planning the assassination.
In act 1, scene 7, Macbeth expresses his reluctance to follow through with the plan, and Lady Macbeth proceeds to ridicule her husband for being weak. She is portrayed as a treacherous, cruel woman who criticizes Macbeth for not being courageous and ambitious. After making Macbeth feel weak and feminine for not wanting to kill the king, Lady Macbeth confidently tells him their plan will not fail. She is sure that the Scottish lords will not discover that Macbeth murdered the king and dismisses the idea of being caught.