A big development in Humans 3.4, one which puts Sam very much in the spotlight of this narrative. It was a logical move, putting him right in the middle of our central characters, but one which I was not happy to see.
That would be the killing of his synth mother, Karen, at the hands of a brutal human mob (who, I can't help saying, remind me of the people at Trump rallies). On the one hand, she was always a marginal character, never quite in the center of this narrative. On the other hand, she was a very appealing and powerful character, well played by Ruth Bradley. I'll miss her.
But her death means that Joe will be taking charge of Sam, which inevitably means Laura and family will be brought into his life, all the more significant in that this family now includes Leo and all of his knowledge. Does Leo know about Sam? Not clear. Indeed, I can't recall who else among our originally sentient synths know about Sam—maybe none of them.
As I said in an earlier review, Sam's very existence raises all sorts of interesting questions, first and foremost being will he age or be an ageless Peter Pan? The actual construction of all the synths is far from clear. Clearly, they have the stuff of circuits inside. We know from season one that they don't digest their food—they live on electrical energy. But it's still not clear if any of them age. Probably not. This would make Sam an especially significant character.
One of the best things about Humans is the way it mixes interpersonal and philosophic issues, along with the action which keeps the story moving. Karen was a victim of this action. Its result has now put Sam on center stage.