When Fouquet walks in, the King is "the most complete picture of despair, hunger, and fear that could possibly be united in one figure."
The King believes Fouquet is there to assassinate him.
Fouquet corrects him – he's there to free the King.
The King knows he will never forgive Fouquet for having seen him in this state.
Fouquet brings the King up to speed on the situation. The King refuses to believe the existence of a twin brother.
The King plans to kill Aramis, Porthos, and the imposter twin brother.
Fouquet points out that they cannot spill royal blood on the scaffold. The King continues to disbelieve that he has a twin.
Fouquet begs the King's forgiveness on behalf of Porthos and Aramis.
The King resists, and Fouquet reminds him of the situation. Fouquet is the King's rescuer. He also reminds the King that Aramis could easily have shot him in the forest, and asks that Aramis be pardoned on those grounds.
Instead of feeling grateful, the King feels humiliated. He refuses to pardon the two conspirators.
As Fouquet and the King leave, Baisemeaux remains completely baffled, even though Fouquet handed him an order showing the King approved the release.