TINA: "I am so sorry about your creatures, Mr. Scamander. I truly am."

NEWT: "I met one in Sudan three months ago. There used to be more of them but they still exist. Before wizards went underground, when we were still being hunted by Muggles, young wizards and witches sometimes tried to suppress their magic to avoid persecution. Instead of learning to harness or to control their powers, they developed what was called an Obscurus."

INT. MACUSA CELL -- DAY

Newt, Tina, and Jacob sitting, Newt with his head in his hands, still in utter despair about his creatures. Finally Tina, on the verge of tears, breaks the silence.

Newt remains silent.

JACOB (sotto voce, to Tina): "Can someone please tell me what this Obscurial -- Obscurius thing is? Please?"

TINA (also sotto voce): "There hasn't been one for centuries --"

TINA (off Jacob's confusion): "It's an unstable, uncontrollable Dark force that busts out and -- and attacks… and then vanishes…"

As she talks, we see the penny dropping. An Obscurus fits everything she knows about the perpetrator of the New York attacks.

NEWT: "There's no documented case of any Obscurial surviving past the age of ten. The one I met in Africa was eight when she -- she was eight when she died."

TINA (to Newt): "Obscurials can't survive long, can they?"

Newt's look says yes.

JACOB: "What are you telling me here -- that Senator Shaw was killed by a -- by a kid?"