[basil ransome-davies]

A start, though I fear it hasn't the Gilbertian oomph.

Macbeth, I, vii: ('If it were done when 'tis done', etc.)

If a dirk while he sleeps ends the problem for keeps
It would pay me to do it instanter.
Yet an act may rebound, though the idea was sound,
Bringing Nemesis on at a canter.
It's a ticklish thing: he's my cousin, my king,
And a houseguest who's due my protection.
What disgrace of a Thane would extinguish his reign
By puncturing Duncan's midsection?
He is good, he is wise, he is praised to the skies
For his modest, appealing demeanour,
Conscientiously keen to be morally clean,
Though my treacherous blade will be keener.
Then once he's no more there'll be weeping galore
For the saddest, most grievous of deaths
And I'll shed my own tears, giving three silent cheers
For the upwardly mobile Macbeths.