From Netflix:

After losing a lot of money to online poker, a Princeton student confronts the site’s shady CEO, Ivan Block — and soon becomes Block’s protégé. But when an FBI agent tries to take Block down, the relationship between mentor and protégé goes south.

Here is your opportunity to see Ben Affleck as the bad guy and Justin Timberlake as the “good guy”. Anthony Mackie is an FBI agent who is another “good guy”. Take that phrase “good guy” with a grain of salt. Makie is just plain ruthless and not beyond murdering in the course of obtaining “justice”. Note how cynical films have become? Timberlake starts out as an intelligent but somewhat naïve Princeton student gambler. Rather than ruthless, he is just plain cunning. Affleck eventually reveals his sociopathic personality.

You more or less have seen this plot in other film incarnations and it is nothing special. But, and correct me if I am wrong, I do not remember Affleck as a villain in any previous film.