The Scottish play” continues to provoke varying interp-retations judging by forthcoming productions. Sam Walters of Richmond’s Orange Tree Theatre finds a problem for both actor and director. “For it to be a tragedy, Macbeth must have nobility before his fall, yet within seconds of arriving onstage he’s met the witches and thinks of being king.” Walters contrasts the character with Iago in Othello, who is evil from the outset. David Mark Thomson, directing at Musselburgh’s Brunton Theatre, agrees: “He’s no psychopath: he has a conscience.”

Yet according to Robert David MacDonald of Glasgow Citizens’ Theatre, Macbeth’s initial mystification at meeting the Weird Sisters soon melts away as he seizes the offered opportunity. However much he is encouraged by others, witches or wife, the fault lies in himself, says MacDonald. “He’s a despot and murderer waiting to happen.”

For all his tortured soliloquies expressing moral reservations over killing King Duncan, once the deed is done Macbeth thinks only of his own security. David Mark Thomson says his dreams “are not of the murder he’s committed, but about Banquo’s sons becoming kings”, while Walters notes one of the play’s longest scenes shows Macbeth preparing hired assassins to kill Banquo. “He spends a great deal of time telling the Murderers why they don’t like Banquo. It’s as if he’s distancing himself from the crime; in the same way he tells Banquo’s ghost, `Thou cans’t not say I did it’.”

Age seems important. At Worcester’s Swan Theatre, director Mark Babych explains: “With actor John Branwell I’ve constructed a Macbeth past his prime, still in the glory of battle but at his last chance with the young Turks coming on.” And MacDonald believes the character’s last act references to “the sere and yellow” are significant. “It’s not just the burden of guilt - he’s prematurely aged.”

MacDonald believes Lady Macbeth finds satisfaction in manipulating her husband: “She absolutely knows what she requires. A lot of people’s ambition is to be the motive force behind something but they don’t want to do it upfront. ”

Babych mixes age and psychological factors: “She’s younger than Macbeth and very manipulative. There’s no fool like an old fool. She loved her father. He died and she married Macbeth as a replacement. She has a child. It dies and she replaces it with a quest for the crown.”

Thomson finds mask imagery in the play and believes Lady Macbeth goes to pieces because, unlike her husband, she “cannot absorb her mask into her psyche. She wants to draw a line under Duncan’s murder; she’s achieved what she wants.”

But it is not as easy as she thinks. Sam Walters sees the murder affecting her long term. When she takes the weapons back to the scene of the crime, she sees Duncan’s corpse. At the time she shows no response, “but the sight must have affected her. In the later sleepwalking scene she refers back to how much blood the old man had in him.”

Glasgow Citizens’ February 13 - March 7 (0141 429 0022), Musselburgh Brunton to February 14 (0131 665 2240), Richmond Orange Tree to April 4 (0181 940 3633), Worcester Swan March 5- 28 (01905 27322)