Our parents can reveal themselves to be several different people over the course of a lifetime. Of course, there is the matter of one’s youth: the stakes of your own existence often feel (fairly) low, pleasure-seeking is the top priority for many, and in so many ways, you pretty much have your whole life ahead of you. But some individuals, as they age, lean into more reactionary or fundamentally conservative social or political attitudes while others remain rebels well into their 80s. For many, as they approach death, there is an overwhelming sense of acceptance in the face of despair — or, to paraphrase Iron Man mega-star Robert Downey Jr., we’re going to discuss the existential ideal: “We’re here, we do stuff, and that’s it.”

Downey Jr.’s complicated, fraught, and deeply loving relationship with his own father – the renegade counterculture maverick known as Robert Downey Sr., who passed away last year — is the subject of Chris Smith’s excellent new documentary Sr. The film functions rather beautifully as a look at how the bond between fathers and sons evolves as they grow older and their priorities change, but it’s certainly engaging, if arguably less ambitious, as a straightforward account of a man, the Sr. of the title, whose own artistic style amid a truly inimitable filmography, was anything but painless.

Smith, the director of Sr., has been churning out good-to-great docs for Netflix for the last few years, including Fyre, a bitingly funny warts-and-all takedown of the Fyre Festival disaster, and the haunting true crime expose, The Disappearance of Madeleine McCann. The closest antecedent to something like Sr. is probably Smith’s breakout picture, the great American Movie, which was similarly concerned with the ways in which creative ambition and "normal family life" sometimes exist at odds with each other.

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Lamenting a lost childhood

Naturally, Sr. functions as a testament to a creative body of work devoted to nose-thumbing irreverence: irreverence, in this case, serving as a kind of raised middle finger to the silly, mostly made-up notion of civil propriety. Yet, the movie is somehow even more interesting as a lament for a childhood that, in so many ways, never got to happen – arguably because the parent in the equation wasn’t fully ready to commit to the idea of being an adult.

While Sr. is certainly the study of a nuclear family for whom making stuff was like breathing, true to its title, the film is undeniably more about Downey the elder than it is about his similarly talented and far more financially successful son. Without Downey Sr., an entire generation of provocative, button-pushing experimental comedy simply would not have taken hold in American culture: you can see the fingerprints of Downey’s aggressively perverse, anything-goes style of guerilla filmmaking in the anti-comedy work of Tim Heidecker and Eric Andre, the first few seasons of Louie (disgraced comedian Louis C.K. is, for better or worse, on the record as being a massive fan of Downey’s most famous satire, Putney Swope), the nervy agitprop of Boots Riley, and even something like this year’s cheerfully gross black comedy, Funny Pages.

Downey Sr.'s legacy

Some of Downey’s early movies are practically impossible to classify at face value, not that anyone would ever want to do such a reductive thing. Take Chafed Elbows, a manic farce about a city oddball entangled in a romantic relationship with his mother. Or how about Babo 73, Downey Sr.’s loosey-goosey, ultra-low-budget 16mm take on a spy flick? These aren’t just movies: they are wavelengths; entire, imagined worlds that you can escape into for an hour or two at a time. As his films moved into the ’70s, the younger Downey started popping up in his father’s movies, hanging out on-set and soaking up the madness whenever he wasn’t in front of the camera. Thus, a bond between father and son, forged in the fires of art itself, was born.

Putney Swope, about an All-Black ad agency in the late 60s that decides to stop manufacturing tools of American death, such as guns and cigarettes, is one of the more unforgettable films of its time: so much so that the subsequent, even more alienating Downey films (the experimental acid Western Greaser’s Palace, 1970s Pound, in which a bunch of human actors play dogs and other assorted animals, and a young, baby-faced Downey Jr. himself gets what could very well be described as his first major movie line reading) really only make sense in a post-Swope context. Sr. touches on some amusing anecdotes and revealing bits of personal history shared between father and son. Downey Sr. revisits a refurbished New York City alleyway where he shot a key scene for Putney Swope, and goes into his friendship with director Paul Thomas Anderson – who Downey Jr. refers to as “the son [his father] wished he had,” and who ended up casting the aging nonconformist as a slick, scowling record company suit in 1997’s Boogie Nights – but as it navigates more serious and sobering thematic waters, the film begins to reveal its truer purpose.

Robert Downey Jr.'s drug addiction

Many movie fans will recall how Downey Sr. slid into a terrible period of addiction and mindless overindulgence, which extended to the director allegedly allowing his son access to free and readily available drugs from an early age. Downey Jr.’s many brushes with the law and struggles with drug dependence early in his career are covered extensively in Sr., but these events are mindfully framed through the lens of a grown man who simply wishes that his father had, at certain points in his life, decided to show up for the son he so often neglected in favor of his art.

But in spite of the baggage his father left him with, Downey Jr. truly did love his dad, right up until the day he passed. Downey Jr'.s heartwarming acceptance of his father, flaws and all, offers a lesson that all of us truly do have the capacity to forgive. Sr., then, is a wildly empathic portrait of two artists – an iconoclast and a movie star – who just so happen to be father and son.