Light Thickens, Ngaio Marsh. New York: Felony & Mayhem, 2016 (originally published in 1982).

Summary: Set once again at the Dolphin theatre as Peregrine Jay stages Macbeth, a play surrounded by superstition, a production plagued by macabre practical jokes, and the real murder of the title character discovered just after the play’s climactic scene, with Alleyn in the front row.

This is the last Chief Inspector Alleyn mystery by Ngaio Marsh, completed in 1982 when she was 86 and just weeks before her passing. She returns to the scene of an earlier murder, the Dolphin theatre, as the accomplished Peregrine Jay undertakes one of the most audacious productions, and one surrounded by superstition–Shakespeare’s Macbeth. The superstition is that it is ill luck for any production members to mention the play by name or speak its lines elsewhere than in rehearsal or performance.

Jay has assembled an brilliant, but eccentric cast. The title character is played Dougal MacDougal, a true Scot and a vain one at that. Both he and his opposite, Simon Morten, who plays Macduff are real-life rivals for the affections of Margaret Mannering, who plays Lady Macbeth. Gaston Sears, who plays Seyton, has an obsession with arms, including the Claidheamh Mòr (emphatically not a claymore according to him), a wickedly sharp two edged sword used in the climactic fight between Macbeth and Macduff. He choreographs and trains them in the fight.

Banquo is played by Bruce Barrabell, a union leader and participant in fringe causes, and has a connection to the child actor, William Smith, who plays Macbeth’s son. William’s father was an insane murderer who killed by decapitation. The most superstitious is Nina Gaythorne as Lady Macduff, although Rangi, a Maori actor and one of the Three Witches rivals her.

A series of incidents arouse superstitions during rehearsals. A costume decapitated head is found in a bag during a rehearsal, and later under a covered platter. A warning message about William and his father is found on the manager’s typewriter. Then the opening weeks of the performance come off flawlessly to acclaim. That is, until Alleyn has front row seats, compliments of the house, after having provided security for some royals attending an earlier performance, and realizes as the climactic scene concludes that something has gone horribly wrong and Dougal MacDougal is really dead, and in the manner of his denouement as Macbeth.

It’s obvious that a number could have a motive and Marsh keeps us guessing until the end while Alleyn methodically interviews witnesses. Yet there is something off in the chronology. There wasn’t enough time for any of the suspects to commit the murder…or was there?

One of the most interesting themes is that of not charging children with the sins of their parents. There are several turns during which William is allowed to shine as his own person, and to be encouraged with the prospects of his future rather than haunted by his father’s past acts. In this, Marsh invites us to heed the better angels of our nature, and to believe the best of others.

Whether this was one of Marsh’s best, I will leave to others. All I will say is that she concluded her last act well.