The ending seemed rushed and anticlimactic, the great blackmailer turned out to be a pretty big disappointment. 
 Lady Augusta was regrettably totally sidelined and underused. It was a pity that her husband, general Ballantyne didn't share his problem with blackmailing letters with her, their marriage was not very successful, but his downfall would concern her, so she deserved to know what could befall both of them. 
 On the positive side, it was good to have more focus on sergeant Tellman's life and his part in the investigation.