When Sam goes to the prison he can see the surprised expressions of those people. Everyone already recognizes Alena, but they do not recognize Sam at first.
"He is the miracle maker of our planet. He is going to read your mind to see if you have any kind of plan or not."
Alena introduces Sam to them. In the next second, you can see all 5 of those people have a scared expression on their faces. Alena did not become that surprised as from the stars you know that every one of them fears Sam. But Sam becomes surprised looking at their sudden expression.
Well, it is normal for those people to become that scared as from the start they wanted to avoid meeting the unknown factor. Currently, the unknown factor is standing in front of them and this is naturally a serious thing.