In the shadow of the black cross, some vows cannot be kept.

When Erwin von Stade arrives at the fortress of Marienburg, he brings two things: a tin of suppressant oil applied every morning for two years, and a body that has been waiting - patient and inevitable - for the moment the oil runs out. He is going to make this work. He has been telling himself this since Hamburg.

Brother Raimund von Eilenfeld has managed four Omegas through their years in the Order without incident. He is disciplined. He is controlled. He has not looked too closely at why he keeps taking the route that passes the training yard at dawn, or why he sits on the same side of the scriptorium table, or why a single candle appeared outside a darkened cell at midnight.

When the suppressant supply fails mid-winter and Erwin's heat arrives ahead of schedule, nineteen years of iron self-control come down to a single hour in a locked stone room - and a bite that neither of them planned.

The partial bond can still be broken. The pregnancy cannot be undone. And the man Raimund is becoming - the one who would burn the Order to the ground before he let anything happen to Erwin - has no place in the Rule of the Teutonic Knights.

He intends to make one anyway.

"Pick it up, Brother." By the last page, neither of them will need to be told.