[John can't speak for several seconds. He just grits his teeth against the pain, face going very pale. Or it would be if there was much more than ambient light from his dropped tablet to see by. It's nearly half a minute before he replies.]

'I'm with you to the end of the line.'

[This movie was two years ago for him, and he saw it once at the cinema, Bucky. What do you want from him?]

HYDRA was studying the Tesseract. I think their experiments were supposed to be part of it. I dunno.