In the midst of celebration, chaos waits in the wings.

After a harrowing Tracker assignment in Scotland, Jess Ballard is finally home and ready to celebrate her twin sister Hannah’s long-awaited wedding—and with Milo at the helm, it promises to be the event of the Durupinen season. But even as they turn their attention to dress fittings, tastings, and last-minute preparations, a cloud looms over them. Tensions in the upper ranks of the Durupinen are coming to a boiling point, and it becomes clear that the wedding itself could well be the crucible in which it all comes to a head.

As the wedding draws nearer, a series of disturbing events has Jess and Hannah worried. Someone is digging into their family’s past, and the reasons are sinister. Hidden deep in the Ballard family history lies a carefully concealed secret—one with the power to reshape the destiny of the Durupinen and their role in the spirit world. If revealed, it could destroy not only Hannah’s walk down the aisle, but the very integrity of the Gateways themselves. Can Jess and Hannah stop this dangerous bid for power—or will the Durupinen’s watch over the Gateways and the spirit world come to a final, devastating end?

Betrayal of the Sisterhood is the 11th installment in E.E. Holmes' best-selling Gateway Trackers series, set in The World of the Gateway.