Like the other great '60s British costume drama about a saint and another Lord Chancellor, a man for all seasons. Lots of parallels.
Hierarchy including episcopacy is God's plan. True Christianity isn't a bunch of whiny teenagers rebelling against Daddy ("question authority, man") like some libertarians. (Jesus couldn't be tricked: we render unto Caesar as long as it's possible.) While we don't have to be monarchists, this form of government (family writ large) is natural and lends itself well to the plan, which is why I respect them. Also, in America we were freer under the King than we are now and morally we were obligated to remain under him; the few grievances didn't warrant the rebellion. (Loyalty oaths to Christian kings matter.)
So it was a wonderful thing when under Constantine, the sin city of the Roman Empire turned around and started to become... entirely Catholic. The beauty of Byzantium. (Putin is a new Constantine, sharing the great caesar's faults, rechristianizing his deeply catholicized empire.)
But of course, what with sin, that solution has always had its problems. Early on, some started mistaking the Catholic empire for the church! The Pope was no longer in the empire, so eventually, adiós, Pope, said Byzantium (and the Byzantium Jrs. such as Mother Russia). And, of course, corrupt churchmen putting money, power, etc. (which buy sex) over God and the people. Complacency is a perennial temptation. Which leads to Henry II and his old drinking buddy/Lord Chancellor (classic Bad Catholics who backslid but never attacked the church's teachings) turned saintly archbishop (primate of England, the realm's ranking churchman), Thomas à Becket.
Christianity is a faith of paradoxes, the God who's one in three, true God and true man, death giving life, becoming incarnate in the world as both the church and Christian society (as the great Anglo-Catholic T.S. Eliot wrote about, as indeed he did about Becket, ironic from an Anglican), yet at the same time God's kingdom is not of this world. On my road back to the church I met the late Archimandrite Serge (Keleher), the former Russian Orthodox priest who explained to me his road back: "in [small-o] orthodoxy there is always tension." Going along with the state too much is one of many errors to try to simplify the faith to relieve that tension. (As are mistaking Byzantium for the whole church and, getting dissatisfied with the official versions, moving to smaller, more exclusive cults of it: ROCOR, Old Calendarists, etc. Convert Greek Catholics, having fallen in love with Byzantium and becoming dissatisfied to the point of leaving the church, are susceptible to that.)
So because of that tension, throughout our history we have a few saints and saints-to-be who have stood up to the authorities only when they had to: the Roman martyrs whose names the priest still recites in the Canon (the second oldest anaphora still in use), Becket, More, Fisher, Clitherow (I have been in her house: I will never look at the Prayer Book the same again) and the recusants, Romža (like the Sultan, the King, and the Tsar, the godless Communists hated the church because they couldn't own it like one could the Orthodox and the Anglicans), Romero (never mind the Catholic Modernists who try to make him a mascot), and the martyrs of Syria today (you don't know how you'll react if ISIS breaks down your door).
Complacency. We American Catholics have always lived in a hostile Protestant host country, not as hostile as the mother country (doubly hostile because it used to be Catholic — Becket! More! — so it's haunted by the church in a way our country isn't) but hostile nonetheless. But the lapsed Protestant/deist founding fathers set up a free country largely to stop the Protestants from fighting each other, which worked for us (and the Jews), and besides, they sort of acknowledged us as the mother church; as Christians we did fit in. (There was once a low-profile colonial English Catholicism in America that survived for generations after independence.) Thus massive immigration from newly emancipated Ireland, the regions of southern Italy, and Poland made a great Catholic home and transformed the country. (Sorry, the French and the Spanish were locally important but not formative nationally.) Understandably it scared the Protestants (battle of the true-church claims, and the Popes were rightly wary of religious liberty) but eventually the Northeast almost became a Catholic "country" ("What parish are youse from?") and our hosts came to love us. We were pillars of the community, uncompromisingly Catholic and patriotically American. Cardinal Spellman's Powerhouse, and God made the Fighting Irish No. 1.
Then late mid last century, it all went, just like that.
The Protestants re-energized, turning into the politically correct (repackaged Reformed religion), and we Catholics, pleased at having arrived in American society, largely went along with their lead. (The Rockefellers bought off Fr. Hesburgh. So much for the Fighting Irish.) Lots of bishops and politicians want to keep having their pictures taken with the president, etc. Authentic Catholic voices are few now, from standing up against invading Iraq last decade to defending true marriage (the problem goes back to contraception, abortion, and no-fault divorce; that movement basically made gays a mascot) to pols really opposing abortion (the world always wins: "Free sex, people!") to decrying materialism/consumerism, promoting the social reign of Christ the King, not the heaven on earth the founding fathers seemed to promise (not just Henry II's selfishness, but a dangerous enemy based on high-sounding principles, just like the Protestants). Churchmen such as Burke (make him Pope) and Cordileone (Lionheart!).
We love our country (God-given love of family, community) but "our country, right or wrong," isn't our teaching, nor is "our government, right or wrong." The church is slowly recovering from its tactical (not doctrinal) sellout of Vatican II (the libcaths are dying out and the lukewarm leave) but it will be a long, slow recovery; we haven't bottomed out yet.
Sancte Thomas, ora pro nobis.