The first time I watched Predestination I believed that a twist would be that Robertson would also turn out to be the same person as Jane/John.
However no clue is given to his identity. The Fizzle Bomber says at the end however:
We're just puppets. We are Robertson. He set the whole thing up. He played us for fools. He's laying out the dominoes. You know, we're just watching it fall.
What does he mean by that line? Is there any clue/theory as to who Robertson is?