In 'Limitless,' Bradley Cooper plays Eddie Morra, a slacker writer who can't wrangle his thoughts to save his life, until an old acquaintance introduces him to a pill that yanks out his brain's hidden smarts. In the blink of an eye, Eddie rises from long-haired slacker ne'er-do-well to corporate bigwig and colleague of one Carl Van Loon (Robert De Niro), learning languages in a flash and managing the market as if he had precognition.

Van Loon, in all of his drug-free smarts, seems like an almost inconsequential player in Eddie's rise to fame, until one day when the weathered businessman confronts Eddie about his capricious behavior. Van Loon lays the smack down on the young, rising talent, reminding him that Van Loon earned his spot in life rather than just stumbling upon it. In that precise moment, we realize that De Niro today isn't the De Niro of yesterday.

There's a knowing look in De Niro's eyes. He doesn't get the chance to do much as Van Loon, but in that moment, the man rises out of the character. He looks us straight in the eye, and lets us know that while he may have one hell of a mediocre career at the moment, De Niro worked his ass off to get to this point. He didn't take the quick route, and he isn't some actor who rides on stolen success. He's still the man who took American cinema by storm.

It's been 46 years since De Niro started his cinematic career as an uncredited diner patron in 'Three Rooms in Manhattan.' Within a decade, he became one of Hollywood's most acclaimed talents, a veritable powerhouse of '70s cinema. This is the man who hit the 'Mean Streets,' dug into life as Vito Corleone ('The Godfather: Part II') and then struggled through the challenges of being a 'Taxi Driver' -- all in a three-year span. This is the man plagued with woe as 'The Deer Hunter,' who soon became a 'Raging Bull.'

But even a new decade couldn't suppress De Niro's talent. Kicking off the '80s with 'Bull,' the actor found everything from the manic science fiction of 'Brazil' to the danger of 'Goodfellas' and menace of 'Cape Fear.' He played Frankenstein, dug into 'Casino' work and played the iconic prisoner in 'Great Expectations.'

But with a new millennium came a new and highly disappointing De Niro. Ushered in by the likes of 'Rocky & Bullwinkle' and 'Meet the Parents,' Robert De Niro was no longer the stunning dramatic actor of his past. For the last 11 years, we've watched the man act as a shell of his former talent, phoning in money gigs in fare like 'Meet the Fockers,' and even dramatic tales like 'Stone.' It's as if Rocky and Bullwinkle stole his interest in the Hollywood game, and he's been on autopilot ever since.

Take the "You talkin' to me?" speech from 'Taxi Driver' -- in one brief scene, he packed more emotional kick and depth then all of his recent movies combined. In moments like this, the sheen of time long-past washes away. We're not digging into a world many decades past, but seeing a man we can journey with now, regardless of our stations in life.

NSFW: Language

This talent even thrived outside of collaborations with Martin Scorsese -- like the pain he evoked in 'Deer Hunter,' when he was forced to play Russian Roulette opposite Christopher Walken. De Niro became a powerhouse because of his charismatic power. Even in moments of stillness, it emanated from him. He wasn't an overtly emotional or audacious character. De Niro was merely a recognizable one -- a man who made each cinematic moment seem like real, heart-wrenching life rather than carefully portrayed entertainment. These skills even earned him six Oscar nominations and two wins (for 'Raging Bull' and 'The Godfather: Part II').

But there's no glimpse of that man today, and it's not only due to the diminishing caliber of the projects he joins. In 'Stone,' De Niro was so devoid of interest that some wondered when he "stopped trying," or even worse, when he became a "pod person." It's as if he's the living embodiment of a Botoxed face -- the passion, emotion and depth masked not behind injections, but a firm distraction. This isn't a talent like Michael Caine or Peter O'Toole, who acted in the dregs of cinema to make a dime and pass the time, men who managed to, even then, make silly productions into worthy enterprises (Ben Affleck wasn't the only bomb in 'Phantoms,' yo).

De Niro is the actor who, God help us, is now digging into Garry Marshall's 'New Year's Eve.' We can hope for greatness with the upcoming 'Red Lights,' which is 'Buried' director Rodrigo Cortes' latest, or maybe that 'Another Bullshit Night in Suck City' will give him humor that doesn't seem agonizingly mundane. But if one considers the last decade, the chances are not good.

The one beacon of light that might just wash away the last 10 years and refuel the acting powerhouse: a reunion with Martin Scorsese on 'The Irishman.' However, as De Niro recently explained, it's on the shelf until Scorsese gets 'Silence' locked.

It's a comfortable, almost-easy piece for the actor -- it's none too shocking to hear that Scorsese and De Niro are teaming up with Joe Pesci and maybe Harvey Keitel to tell the story of Frank "The Irishman" Sheeran, who claimed he killed Jimmy Hoffa. But at this point, who cares if it's old hat for the talent? If this production can give us even one more glimpse of the old De Niro, the one that makes us quake in our boots in fear or respect, I say give De Niro a bigger gun and let it happen. His audience is desperate for it.