Asa Butterfield, Gillian Anderson in 'Sex Education'
CNN  — 

The reliance on U.K.-produced TV shows to flesh out US lineups – especially on the streaming services – is on full display this month, with the latest wave of this British invasion involving quartet of series making their debuts on Netflix, Amazon and Hulu, including a pair that deal frankly with teen issues.

The most distinctive of the newcomers deal with youth-centric stories, albeit in decidedly different ways.

Netflix’s “Sex Education” is about a teenage boy (Asa Butterfield), who has acquired detailed knowledge of sexuality thanks to his sex-therapist mother (“The X-Files’” Gillian Anderson), although that’s merely a jumping-off point for a whole lot of awkwardness and discomfort.

Easily more interesting – and certainly more emotionally engaging – is “Butterfly,” a three-part miniseries about parents coming to grips with the challenges presented by their transgender 11-year-old Max (Callum Booth-Ford), who announces that she wishes to be known as Maxine.

The situation, and how to handle it, has created a rift between the parents, played by Anna Friel (“Pushing Daisies”) and Emmett J. Scanlan. Nor does it help when they seek counseling, and the father compares the prospect of his son becoming his daughter to the way he might feel if the child had leukemia.

“I want to feel happy,” Maxine explains to a therapist, in one of several heartbreaking moments that “Butterfly” – written by Tony Marchant – produces over the course of three episodes that total roughly the length of a longish movie.

Callum Booth-Ford in 'Butterfly' (Photo by: Ben Blackall)

“Sex Education,” by contrast, feels a little too intent on shock value – with lots of teenage grappling, and a well-endowed character dropping his pants at school – without establishing characters that resonate much in the early stages of its eight episodes.

This month’s other British invaders are both dramas: “Informer,” about a London-born man of Pakistani descent, ruthlessly coerced into becoming a counter-terrorism operative; and “Black Earth Rising,” a series about prosecuting war crimes at the Hague, starring Michaela Coal and Harriet Walker. (John Goodman plays a supporting role, offering a familiar face to an American audience.)

American TV subscribers have clearly benefited from greater access to overseas productions, while networks find original content at a more affordable price than most of their commissioned offerings. In that sense, the influx of British series – as well as programs, some of them subtitled, from other countries – is a win-win.

Still, after a period where the best of Britain’s best landed on “Masterpiece Theater” – and little else was available – the surge in series imports has inevitably diluted some of that patina of quality.

The new shows are so different in tone and topic that each will have its own constituency. But based on a sampling of all four, the heartbreaking “Butterfly” is the only one that really takes off.

“Sex Education” and “Black Earth Rising” premiere Jan. 11 and Jan. 25, respectively, on Netflix.

“The Informer” and “Butterfly” premiere Jan. 11 and Jan. 18, respectively, on Amazon and Hulu.