Promises Stronger Than Darkness is a 2023 science fiction novel, the final installment in the Unstoppable trilogy by Charlie Jane Anders.

[1] The book picks up after the end of Dreams Bigger Than Heartbreak, where Tina Mains' body has been taken over by galactic war hero Thaoh Argentian, who she was cloned from.

Rachel and Elz struggle to adjust to the loss of Tina as the Bereavement threatens to destroy the galaxy.

[3] Kirkus Reviews wrote that the book "showcases Anders’ layered worldbuilding and emphasis on interpersonal relationships.

"[4] Nerds & Beyond also praised the book as a conclusion to the trilogy, writing that it was "just as rich and imaginative [as earlier instalments], with a magnetic universe filled with wonder.>[5]