There are no yearning, tasteful violins in Cliff Martinez’s score for “The Knick,” which continues to avoid the obvious period drama trappings as it returns in bracing form Friday. And yet Martinez’s music, like the show itself, positively pulses with life.

The electronic soundtrack may reflect the chilly brutality of the world the show’s turn-of-the-century characters live in; immigrants and upper-crusters alike find rejections and obstacles at almost every turn. The operating room continues to resemble a gladiatorial pit, one in which gloveless doctors root around in unsightly cavities. Treatment at the Knickerbocker Hospital, like the show itself, is not for the faint of heart (or stomach).

And yet it didn’t take long for “The Knick,” which debuted last year, to establish itself as one of television’s most vital and thrilling dramas, and it builds on last year’s strengths capably in season two. “The Knick” has what tamer period dramas lack: A spark of life and sense of danger.

Martinez’s music is essential to setting the show’s mood, which travels smoothly from apprehension to contemplation to an amused appreciation of transgression. The jittery score transmits the sense of excitement these men and women feel every time they make a discovery, medical or otherwise. Many of these characters become convinced, at various points, that they have stumbled upon something big. An answer to an age-old question, a philosophy that will ensure a brighter future for the nation, a cure for a terrifying disease, a way to feel washed clean of sin or a trick that will ensure a big payday — they hope or just know these momentous events or discoveries are just around the corner. With patience and economy, “The Knick” surgically peels back layers of obsession and delusion, until the pain and insecurity beneath the characters’ aspirations are fully revealed. And yet the Cinemax drama never sits in judgment of these surgeons, nurses, strivers and socialites. The curiosity “The Knick” displays, in the end, is a form of compassion.

Director Steven Soderbergh is profoundly interested in these people — not just in their goals and actions, but in their emotional states. His camera is restless and roving in Manhattan street scenes and in sketchy dives and well-upholstered clubs, some of which in 1901 are lit up with newfangled electric lights.

But “The Knick” also expertly deploys silence and stillness; the camera loves to dwell on the faces of characters hearing bad news or reacting to unexpected revelations. In one scene, Juliet Rylance’s socialite character almost silently absorbs the unexpected arrival of her creepy father-in-law, whose interest in her seems anything but familial. Her father-in-law and husband pay almost no attention to her words or facial expressions, but viewers quickly see her travel from revulsion to fear to a stubborn, even hopeless, resolve.

Dr. John Thackery (Clive Owen), the disgraced former head surgeon at the Knick, is frequently so self-absorbed that other people barely register to him as anything other than co-conspirators or problems to be solved. Thackery’s most troubling addiction — even more ruinous than his love for cocaine and heroin — is his belief that he can find cures for diseases through sheer force of will. But much of what makes “The Knick” tick rests on this question: Maybe only unrealistic people can make the impossible happen?

There is no sentimentality in the depiction of Thackery’s selfishness or in the difficult progress of the Knick’s only black surgeon, Dr. Algernon Edwards (André Holland). The former nun in jail for having performed abortions has no illusions about her situation either. And truth be told, sometimes the scripts hit certain signposts in a somewhat predictable fashion. (Who would have guessed that the mediocre white doctor outranked by Edwards would become an adherent of eugenics? Well, anyone watching the show, probably.) But as was the case with “Deadwood,” a period show with a similar sense of unpredictable vitality, the point here is not the plot, but the people.

Owen is clearly relishing playing a character who looks haggard and half-demented a good deal of the time; Thackery’s almost toxic commitment to medical research gives Owen a great deal of room to explore the man’s stoicism, his drive and his ability to deceive himself. The odds that a man with a raging addiction problem will be able to find a cure for heroin and cocaine dependency are not high, and yet it’s hard not to be engaged by Thackery’s wild-eyed sense of possibility.

Drug problems, racism, anti-immigrant bias, corruption and the confining rules that serve an oppressive status quo; nothing about these characters or their problems feels all that removed from the challenges that crop up in our own day and age. And yet “The Knick” is one of the most weirdly optimistic series on TV. Connections are made, often where they shouldn’t be (at least according to society’s rules), and just when you least expect it, the show will supply a lovely tableau right out of a Toulouse-Lautrec painting. “The Knick’s” roving eye is searching for beauty and kindness too, and sometimes finds it.

The lack of artifice and sentiment in the way these stories are told is ultimately what helps give “The Knick” its compassionate vigor. This show is always paying attention, always figuring out what characters are trying (and often failing) to suppress. Its characters may be buttoned up in corsets and waistcoats, but the world of “The Knick” is recognizably unruly and reliably complex.

TV Review: ‘The Knick’ Season 2

(Series; Cinemax, Fri. Oct. 16, 10 p.m.)

  • Production: Filmed in New York by Ambeg Screen Products, Anonymous Content and Extension 765.
  • Crew: Executive producers, Gregory Jacobs, Steven Soderbergh, Michael Sugar, Clive Owen, Jack Amiel, Michael Begler; co-executive producer, Steven Katz; producer, Michael Polaire; director, Steven Soderbergh; writers, Amiel, Begler; camera, Peter Andrews; costume designer, Ellen Mirojnick; production designer, Howard Cummings; editor, Mary Ann Bernard; music, Cliff Martinez; casting, Carmen Cuba; 55 MIN.
  • Cast: Clive Owen, André Holland, Juliet Rylance, Eve Hewson, Jeremy Bobby, Michael Angarano, Chris Sullivan, Cara Seymour, Eric Johnson, David Fierro, Maya Kazan, Grainger Hines, Leon Addison Brown, Tom Lipinski, Charles Aitken, Jennifer Ferrin, Rachel Korine, Michael Nathanson, Andrew Rannells, Zaraah Abrahams, Annabelle Attanasio, Arielle Goldman, Emily Kinney, Lucas Papaelias, Gary Simpson, Perry Yung, Ben Livingston.