Siena Rosso

Siena Rosso is an opera singer carving out a life on her own terms in Regency London's demimonde, where a woman's voice can win her admirers but never respectability. She catches Anthony Bridgerton's eye and holds her own against his rank, clear-eyed about what she stands to lose and unwilling to be anyone's secret shame.

Bartlett plays her with a guardedness that never curdles into bitterness — she's sharp about the bargain society offers women like her, and she names it plainly instead of suffering prettily. The show could have made her a plot device for Anthony's arc; instead she reads as someone with her own appetite for a life worth having.