Denzel Washington has become the oldest working movie star in Hollywood. Other older actors, from Robert De Niro to Robert Redford, carry clout and may still get leading roles sometimes. But Washington remains a star with a capital S, with vehicles sold almost entirely on his presence. He has mostly used that star power on action movies that are more commercial in nature than artistic. But, Washington, who turns 63 next month, has also lent his weight to recent projects that have commanded critical acclaim, earning Best Actor nominations at the Oscars for last year's Fences (which he also directed) and 2012's Flight. Roman J. Israel, Esq., a straight up drama, is along the lines of those two films. Like them, it showcases a substantial and inspired lead performance by Washington, who will no doubt also make this more of a mainstream attraction than any of his contemporaries would have.

In his follow-up to Nightcrawler, writer-director Dan Gilroy casts Washington in the title role. Roman J. Israel lives and works in present-day Los Angeles, but you wouldn't know it from looking at him. Israel sports an Afro and suits that were last in style in the 1970s. He doesn't own a car, nor does he treat himself to anything more extravagant than peanut butter sandwiches he eats standing up. It's not just Israel's fashion sense that is out of date. The public defender clings to social values that rose to prominence in the 1960s and '70s. Knowing legal codes by heart, he is as principled as any attorney and committed to his clients, recognizing that the system is often not fair towards those he represents.

Israel is the brains of his law firm, letting his fellow partner, the firm's face, do the defending in court. When the partner suffers a heart attack, Israel is forced to take the cases to court and cannot bring himself to settle for the continuances he is advised to request. When the partner becomes comatose and unlikely to ever recover, Israel resists the firm's dissolution before accepting a position at the large, prosperous law firm of George Pierce (Colin Farrell), who was mentored by Israel's partner and consulted with him.

Predictably, Israel is not a great fit with his new employer's culture, but everything changes when a juvenile client facing charges for a murder he didn't commit ends up dead and Israel decides to report the whereabouts of the fugitive who actually pulled the trigger. The lawyer's anonymous call improbably leads to an arrest and a quick $100,000 cash reward from an angered Armenian society whose leader was a relative of the slain.

Just like that, money changes Roman Israel. Gone are his baggy old polyester threads and foam headphones, replaced by custom-tailored suits and the noise-cancelling Sony version of Beats by Dr. Dre. He hits the beach with a fancy drink and maple bacon donuts, checks into a nice hotel, and looks at a new luxury apartment building. That 'fro gets combed down to something more presentable. The big civil action lawsuit on plea bargain reform that he had been working on gets sidelined. And Pierce, though initially irate that his firm may be susceptible to a malpractice suit, embraces the newly civilized and contemporary Israel, even having him head up a new pro bono division after his people skills net the group more clients.

But as the legal document Israel is drafting in the nonlinear opening scene hints at, professional advancement comes with complications, as the lawyer questions the compromise. His sliding moral scale has an effect on a relationship starting to bloom with fellow advocate of the people Maya (Carmen Ejogo). There are also consequences to that phoned in reward.

Like Nightcrawler, Gilroy makes Roman a one-character study that reflects upon modern living as a whole. Whereas his directing debut focused on a creepy crime scene photographer (a performance many felt Jake Gyllenhaal should have been Oscar-nominated for), this one lets Washington sink his teeth into an anachronous attorney. It's a compelling protagonist worthy of spending two hours with. His evolution is rather abrupt and may be hard for some viewers to swallow. So too will the ending, which changes the tone of the film to less detriment than Nightcrawler's final act did.

In his more than thirty years as leading man, Washington has proven himself again and again to be a charismatic and magnetic leading man. He's not much of a chameleon, though, which makes his work here some of his most interesting to date. Farrell is also compelling in a role that initially strikes you as one-note but also is given room to grow.

Roman Israel has a difficult task of winning over a cynical public with a tale of outdated idealism giving way to...well, pragmatic cynicism...in the course of something like twenty minutes. Not every moviegoer and critic will be able to buy into that transformation. But the film was much too engaging for me to mind as it changed gears or pursued certain threads to only semi-satisfaction. I was too hooked by Washington's characterization to bristle at the arc or object to its unpredictable trajectory.