‘The Enemy Within’ is a good episode, and the start of internal problems. While Teal’c is being held by the Government, Kawalsky ends up with a snake in his head. As they fight to save his life, he is eventually lost to them. The Goa’uld that takes over attempts to escape, but Teal’c manages to hold Kawalsky partially in an open gate while it’s closed, killing him. Teal’c act here helps the government into trusting him and allowing him to join SG-1.
I think that this was a wonderful episode. The acting was grand and the plot helped teach us a little about the way Goa’uld are, and how the government is going to react to the alien things that are brought through the gate. Overall, it is one of my favorite episodes, and I wish they could have many more as good as this one.