The set-up, which is gradually unfolding over the season, is that there are a least four kinds of androids in this near-future London, where the story takes place. In ascending order (that is, in order of increasing correspondence to human intelligence) -
1. Odi, Dr. Millican's android, prized by him for sentimental reasons (Odi remembers his wife), is the most primitive. His model is breaking down and being replaced by "better" creations.
2. Vera, Odi's replacement, is such an improved model. So is Anita, the most important in the story so far, and her story is far more complicated. She's actually far more advanced than Vera, and is sentient (see #3 below), but she was kidnapped and outfitted with a #2 overlay (which, of course, is not completely effective). She's purchased by Joe Hawkins for his family, and they unsurprisingly have very mixed reactions to this gorgeous new addition to their home: Joe's wife Laura is suspicious, daughter Mattie is a brilliant hacker and able to pry out a little of what's deep down in Anita (her earlier sentient identity as Mia), and son Toby has the hots for her - but it's Joe who avails himself of the "adult" option and sleeps with Anita.
3. In addition to Mia, there are at least four other sentient androids, including a beautiful blonde with a taste for killing humans, which put the police on her trail. Apparently all five of these sentient androids must be on hand in order for their master plan to proceed - this according to Leo, son of the main inventor of the androids (who fired Dr. Millican, and who subsequently died). Leo is himself a cyborg - that is, a human with significant digital wiring - applied by his father to bring him back to life after drowning.
4. There's a police officer who's also a sentient android, but not one of the five. Whether she's the same as those in #3, or something different or more, is not clear at this point. (I did realize she likely was an android before it was revealed, because she had a slightly mechanistic posture - tribute to good acting.)
The show is literate, sensitive, and intelligent. Niska, the blonde android, is reading Arthur Koestler's The Ghost in the Machine in one scene (great book). Someone mentions "Asimov blocks," a reference to Isaac Asimov's famed three laws of robotics (later four, when he added a zeroth law) to the effect that a robot can never by action or inaction allow harm to befall a human (and in one of the best scenes, Anita following this programming puts her body in front of a car to save Toby). There's continuous flirting with the paradox of the liar - if you ask a liar is he's telling you the truth, or if it's true that he cannot lie, how can you take yes for an answer? And the acting is fine - especially good to see William Hurt as Millican, and Tom Goodwin-Hill from Mr. Selfridge as Joe.
In short, highly recommended (and, for its worth, far better than Almost Human on Fox last year).
different kind of humans