“The Card Counter” is Paul Schrader’s follow-up to his superb “First Reformed”, and it continues his thought-provoking and sincere exploration of guilt in contemporary America. As with Ethan Hawke in the previous film, he has found the ideal actor for the lead role in Oscar Isaac. Similarly, the climactic scene is truly shocking, a totally unexpected yet satisfyingly lucid summation of Schrader’s main theme. If the dramatic narrative that took us there is a little bumpy, and slow, it is still worth the wait.

Isaac plays William Tell, a sly twist on his given name, and we see him first in military prison. We learn that he is a soldier convicted of prisoner abuse at Abu Ghraib, a term of eight years. He passes the time playing poker with the other inmates and, based on his supreme skill counting cards, he decides to make that his profession when released.

But we learn almost nothing about his former life through the course of the film. We see a mostly silent, inexpressive man, living out of a suitcase, driving from game to game through flat landscapes. Tiffany Haddish plays La Linda, a card sponsor who sees him as a winner, but he rejects her offer at first. But then he unexpectedly meets Cirk, who recognizes him as one of the soldiers jailed for torture at Abu Ghraib, like his father. Cirk tells him that prison ruined his father, who beat his mother, and drove her to abandon him before eventually killing himself.

Cirk also reveals that his goal in life is to confront Major John Gordo (Willem Dafoe), the private contractor who directed the torture program. Gordo received immunity because he wasn’t in the military at the time, but Tell and Cirk’s father had to go to prison. Tell recognizes that Cirk wants revenge against Gordo, which could only lead to his getting killed. But he sees the boy won’t listen to him. He contacts La Linda, and agrees to a deal where Cirk will go with them to games; the idea is for him to learn poker to pay off his debts. But also to make him forget about Gordo.

Willem Defoe plays Gordo, and he’s very underused. But his main function in the story is to hold us to the expectation of a violent confrontation with Tell. This is what happens, and Schrader’s brilliant use of suggestion, both visually and in sound design, makes our imagining of the violence more powerful than showing it outright.

However, the developing relationship between the three principals – Tell, La Linda and Cirk – is strained. While willfully celibate since his release, Tell’s growing attraction to La Linda is strictly formula, almost rom-com, and their eventual coupling doesn’t advance the story either. In fact, it plays out more like an homage to the ending of Bresson’s “Pickpocket”.

And Cirk muddies the narrative further. The subtext is Tell’s feelings of responsibility for the boy as tied to his unexpurgated guilt for his crimes. While this could be dramatically strong, Cirk is too underwritten a character to convince us of this. Tell tries to use Cirk in order to suppress his own drive to kill Gordo. The entire gambling fixation is just a ruse – and not a thrilling one cinematically – which we foresee that Tell will eventually turn his back on when a sudden, and rather confusing, plot twist forces him to finally confront Gordo.