As we spent time with the families of these murderers, one thing was clear: their lives had appeared normal up until the point they killed someone, with no warning signs of what was to come. Unlike men, most women who kill have no history of criminality. Their crimes seemed like aberrations, moments of madness.
After the first episode, we were left with the pieces of a challenging jigsaw scattered all over the floor - with not much idea how they fitted together and whether they were all part of the same puzzle. The writers provided us with a few theories that left seasoned crime drama viewers saying "That's far too obvious", so we are certainly in for an interesting ride as the series unfolds.
If you want to help Brendan Cox, or any bereaved friend, remember that the pain goes on for them. And on, and on, and on. You can help. Just be there. Take them out, let them cry, realise that they are a newborn trying to find out who they are going to become now that the world has ended. They will remember your kindness (or your stupidity) forever.
The attack is also a symptom of the aggressive politics we have basically come to accept in the 21st Century. Many elected representatives receive abuse, often daily. Campaigners, advocates, even Twitter users are frequently subject to both verbal and physical abuse. This has become normalised - and it shouldn't have. We are all to blame for that. We must address this.
Through examining 10 cases in Murderers and their Mothers, I have begun to unpick the complex fabric of the killer by pulling at the "mother" thread. Why such an emphasis on mothers? What about the fathers? Isn't this sexist? These are questions that I have encountered a lot over the past few months.