It is one of the problematic plays of Fletcher's oeuvre; as with Love's Cure, there are significant uncertainties about the date and authorship of Thierry and Theodoret.
Early critics attributed the play to Beaumont and Fletcher, Philip Massinger, Nathan Field, Robert Daborne, John Webster, and George Chapman, in various combinations.
[2] Most modern scholarship accepts the play as a work originally by Beaumont and Fletcher that was later revised by Massinger, comparable to Love's Cure, The Coxcomb, and Beggars' Bush.
Theodoret is reproving his mother for her licentious and libertine lifestyle, criticisms that Brunhalt rejects; she accuses her son of disrespect in merely broaching the subject with her.
In the second scene, Theodoret is shown in consultation with his virtuous councillor Martell; the play presents the French king as a dedicated and upright ruler.
(The scene constructs a personality portrait of Thierry that prevails through the rest of the play: he is passionate and given to overblown language, but highly impressionable.)
The characters' attention shifts in response to the news that Thierry's fiancée – the fifteen-year-old princess Ordella, daughter of the King of Aragon – has arrived.
To buoy his reputation, Brunhalt's sycophants pay De Vitry, an old soldier down on his luck, to challenge Protaldie in public and then take a beating from him.
The passionate Thierry is so outraged that he wants to burn down his own palace around the body as a funeral pyre; Brunhalt talks him out of this plan by admitting that she is responsible for the murder.
Brunhalt complains about her son marrying what she calls a gardener's child; but Thierry thinks he can make up for the girl's loss of a father.
The play's plot is based on the careers of Frankish rulers of the late 6th and early 7th centuries, Brunhilda of Austrasia and her grandsons Theuderic II and Theudebert II (transformed in the play into Brunhalt and her sons Thierry and Theodoret), but their soldiers are armed with muskets, and the characters observe the gods of Ancient Greece.