Don't listen to the misogynists who get upset when women do science - they're called scientists just like their male counterparts. Grow up.
The documentary starts in the days when black holes were theoretically possible but improbable, to the conclusion (always provisional in science) that black holes may be what makes galaxies, and therefore us, possible. Along the way, we were treated to the history of how the first black hole (Cygnus X-1) was discovered and finally proved beyond reasonable objection, and then to the work which showed that (probably) every galaxy has a super massive black hole as a seed.
Great job and Janna Levin is a great presenter.