Senso is a member of the Hidden Ones - a race of human and Inhuman crossbreeds with the powers of mental persuasion. Their race was subjugated by the Nazis, and Senso was tortured and attempted to be turned into a weapon of war.
After their escape, Senso and the others agreed to infiltrate human society in order to manipulate them into never locating their race again.
Senso would infiltrate the Unites States military and the Guardsmen to launch an attack on the Inhumans. She believed that if the government began searching for the Inhumans, they would find the Hidden Ones as well.
Senso proved her high intelligence by disabling Mr. Fantastic's security systems. This allowed for the Invisible Woman and her allies to be attacked by Senso's forces and at a most desperate time for Sue Storm Richards, as she was in the midst of extreme labor pains. Sue pleaded for Reed to come and help her, but Senso's energy blast knocked out Mr. Fantastic, thus assuring that he would not be available to help the gorgeous blonde during her crisis.
Her plan was thwarted by Mr. Fantastic and the Fantastic Four and Senso escaped back into hiding.