Every character in the play Macbeth suspects or is suspected. Elaborate.
In Shakespeare's Macbeth, fair is foul and foul is fair, as the witches declare and Macbeth echoes. This theme is prevalent throughout the play.
Duncan thought the original Thane of Cawdor was a man he could trust absolutely, but he was a traitor. Lady Macbeth should be a caretaker and mother and hostess, but she wants to be aggressive and bloodthirsty like a male warrior. Macbeth should be a loyal thane, but he's a traitor, too.
With oppositions dominating the play, it is no wonder suspicions are aroused. Banquo is beyond reproach, but Macbeth has no trouble convincing the two murderers that it was Banquo that wronged them, not Macbeth. Macduff, too, is beyond reproach, yet Malcolm suspects him of being a collaborator with Macbeth against the well-being of Scotland.
Ironically, however, it is the lack of suspicion that leads to the crisis in Scotland in the first place. If King Duncan was less gullible and a little more suspicious, he'd have protected himself better, or not stayed at Macbeth's castle in the first place. Unfortunately, he didn't learn his lesson after the original Cawdor's betrayal.
Throughout the play, characters have their suspicions about other characters and the roles that they have played in ill acts. For example, during his conversation with the old man, Macduff reveals that he thinks Macbeth has had a hand in the death of King Duncan. As a result, Macduff refuses to attend Macbeth's coronation. Similarly, Banquo suspects that Macbeth has done evil things to become king. Macbeth, on the other hand, suspects that there are men in Scotland who are out to overthrow him, hence the string of murders that he commits. Just as Macduff and Banquo suspect Macbeth, he suspects them.