Answer:
My second is performed by my first, and it is thought a thief by the marks of my whole might be caught.
Someone walked into a room and you heard a crash! Someone died. What happened?
Though blind as well, can lead the blind well.
Everyone has it and no one can lose it, what is it?
I am cracked by Indiana Jones. What am I?
You use it between your head and your toes, the more it works the thinner it grows.