Post-movie, Tina's in charge of an investigation on a wizarding crime ring that involves magical beasts - maybe they're smugglers, or maybe they're Grindelwald supporters using them in terrorism somehow. It culminates in a struggle at the criminals' base of operations, where they attempt to use a hostage as leverage.

Turns out, the hostage is Newt.

He had been after the same group, trying to rescue the creatures they were abusing, but they were able to get the upper hand and capture him. So now this is suddenly very, very personal for Tina, but she has to keep a level head and rely on her Auror training if she wants to get them both out of this alive.