Middle of the second episode of His dark materials (BBC One), the immense adaptation of the BBC to the enigmatic novels of Philip Pullman Mrs. Coulter (Ruth Wilson) has outfitted her young protege Lyra (Dafne Keen) for a party dress. Lyra, who has found her new environment more enjoyable than Jordan College, is reluctant. Coulter answers that the clothes you wear determines what people think about you. The friction between the two women grows.

We could have added that you can see even more by the taste of someone in the interior. Everyone can put on a dress for a night. Furnishings and furniture are a much more reliable personality test, the sum of a thousand small decisions. Mrs. Coulters Gaffel is a pure oligarchs psycho: marble corridors, designer chandeliers, oppressive bedrooms, absolutely no mess. Lyra does not need an alethiometer to find out who the wrong person is. She could only look at the curtains.

Coulter assures Lyra that she's doing everything in her power to track down Lyra's missing friend Roger, but the girl would rather join the hunt herself. She sneaks through her lush new apartments and hears suspicious information. Slowly she realizes that she is a prisoner.

Elsewhere in Old Oxford, the machinery of the property is in full swing. The guerrilla efforts of the Egyptians to free the children cause the magisterium a headache. When Master (Clarke Peters) refuses to cooperate with Lord Boreal's (Ariyon Bakare) investigation, Boreal decides to go to the other side of the real Oxford, which has worse clothes, better coffee and a neat update of the books, smartphones. Compared to the steampunk elegance of the imaginary universe, ours is crass and loud.

The central revelation about the identity of Lord Asriel (James McAvoy), is inelegantly done. Coulter has been upset by the arrival of a couple of goons from the Magesterium, who threaten to shut down her research. When Lyra confronts her afterwards, Coulter sets her vicious monkey daemon on Pantalaimon. It is a one-sided proxy conflict, an act of pure bullying, and in the aftermath Coulter blurts out the truth. Keen is an expressive physical actor, but less convincing in the angry moments that follow.

There are a couple of other clunky notes, such as when Coulter tells Lyra about her fear of heights. But perhaps programmes made with children in mind must signpost some of their beats more clearly than an adult series. In a way, it’s a compliment. Because the look, feel, scope and imagination of the series are equal to the glossiest of HBO dramas for adults, it’s easy to forget this is meant to be dark material for the whole family.