Evelina Detweiler was a Mesan citizen and the wife of Albrecht Detweiler. (HH11)
She was considered one of the Mesan Alignment's top researchers in the field of bioscience, and was an expert in bioweapons. Her husband considered her the epitome of the "absent-minded professor". (SI2)
In mid-1922 PD, she and and her husband intended to leave Mesa, but the Grand Alliance's invasion fleet commanded by Admiral Gold Peak arrived before they could do so. Albrecht and Evelina then committed suicide by detonating nuclear devices all over the surface and in space above Mesa to keep any remaining proof of the Alignment's presence in the Mesa System from falling into enemy hands. (SI4)