To Samuel: "I learned some... tricks over the years as my studies have taken me out of the realm of the strictly mundane. I can go into more detail when we're not around the prisoner."
To the group, away from the prisoner: "I have a bit of an understanding of how these sorts of things work, but there is just... so much to learn. And the more I learn of it, the less sense everything else makes. It's rather disappointing to see twenty years of scientific study become somewhat obviated.
As for the 'tricks', I can turn myself into a hawk or rat, banish creatures from the other realm out of this one, 'burn' things, for lack of a better word; it's not really fire. I can gain some control over the minds of others, usually as a distraction or to make them more friendly or receptive; it's not actual mind control. I can make people see or hear things that aren't there, view a location remotely, and provide some amount of physical protection for myself.
Now, some of these things I only have a passing knowledge of, and they all come at a bit of a... cost. Using them tends to weaken me and give me one hell of a headache. It's why I usually stick to more traditional methods of investigation. Given what we're up against, I may be in for some more headaches, soon."
OOC: By this point, working with Elizabeth, you would know she has some knowledge of these types of things, but you might not have seen her cast a spell directly. She does so sparingly.