The callbacks in 'Creed II,' for people who haven't seen the original 'Rocky' movies

Warning: Spoilers from "Creed II" ahead. (Also for"Rocky II" and "Rocky IV," but you've had plenty of time to watch those.)

The critical and commercial success of "Creed," which reinvigorated the "Rocky" franchise, meant a lot of people who watched the Michael B. Jordan-led film weren't so familiar with Sylvester Stallone's boxing universe. But the Ryan Coogler-directed 2015 movie found a balance between homage and freshness, so the audience could enjoy seeing the ascent of Jordan's Adonis Creed without knowing much about the previous "Rocky" movies.

But "Creed II" feels very much like a "Rocky" sequel. Although the characters say enough about the past to give you context along the way, much of the movie serves as one massive callback to the original movies.

The "Creed" series comes out of the events of "Rocky IV." In the 1985 installment, Apollo Creed dies during a fight with Ivan Drago, the Soviet-trained iron post of a man. Rocky Balboa, who was in Apollo's corner, is riddled with guilt and decides to fight Drago. He not only wins, but in a post-match speech, sort of ends the Cold War?

Fast-forward to present day, and Apollo's son, Adonis, is still living under the weight of his legendary father's tragic death. In "Creed II," he gets a chance to fight Viktor Drago, Ivan's son.

Here's a rundown of the callbacks in "Creed II."

Why even bother?

Ahead of his first bout with Viktor, Adonis tells Rocky that he has to take the fight, that he has no choice. Rocky reminds Adonis that his father said the same thing, and then he died in Rocky's hands.

This is true! In "Rocky IV," a younger Rocky tries to talk Apollo out of taking the exhibition match. It's not even for a title, it doesn't mean anything and, plus, they're old guys now, not able to fight as they once did. "You and me, we don't even have a choice," Apollo snaps back. "See, we're born with a killer instinct that you just can't turn off and on like a radio. We have to be right in the middle of the action."

That was enough to win Rocky over the first time, but this time around, the old champ is not supportive of Adonis's argument.

I thought we were supposed to talk about big decisions.

Rocky doesn't consult with Adrian about taking the fight. And Adonis doesn't consult with Bianca about whether to take that first Viktor fight. Both seem like pretty bad partner moves.

We're pregnant!

In "Rocky II," Adrian and Rocky get hitched. She gets pregnant soon after but slips into a coma after prematurely giving birth. In "Creed II," Adonis and Bianca also decide to get married. Later, she gets pregnant, and Bianca and Adonis have their own health complication to confront.

Fight locations

In "Rocky IV," Team Drago won't accept a fight unless it takes place in the Soviet Union. "We have threats of violence," his wife says at a news conference. "We are not in politics. All I want is for my husband to be safe ... You have this belief you are better than us. You have this belief that this country is so very good and we are so very bad."

In "Creed II," Adonis takes the rematch in Moscow. In both movies, the Americans get a pretty hostile reception.

Let's get buff

It's not a "Rocky" movie without some crazy workout montages. This time around, Adonis heads to what's described as hell to train for his big fight. (We're not sure why a desert climate provides the ideal conditioning setting, but it's extreme and working out is generally miserable, so why not?) Adonis stays in a crappy shack and completes inefficient, arduous tasks, like digging a ditch in the desert landscape by pounding the ground with a sledgehammer. But while Adonis fights with one foot inside of a spare tire, Viktor is training in a gym with weights and battle ropes.

This all mirrors the training in "Rocky IV." In that sequel, Rocky heads to the Russian wilderness, where it's bitterly cold - Is extreme weather even useful for boxing prep? Can someone please advise? - and stays in some rundown cabin. He gets his reps in by lifting horse carts, chopping down trees and scaling mountains. Ivan, on the other hand, is hooked up to what passes as 1980s-level high-tech equipment, runs on treadmills and uses step machines. (However, Ivan seems to be doping, while we get no sense of drug use by Viktor.)

Twist the towel 'round your head, like a helicopter

So much of the drama in these boxing movies revolves around the towel. Yes, it can soak up blood and sweat, but by throwing a lowly rag into the ring, you can stop a fight and potentially save a life!

In "Rocky IV," Apollo refuses to let Rocky throw in the towel "no matter what." The decision to not go against Apollo's wishes ends up killing the boxer, and Rocky is still haunted by his choice. In "Creed II," Rocky, who refused to train Adonis for his first fight against Viktor, watches the match on TV and yells for the trainer to throw in the towel. But during the second fight, Rocky, who has now trained Adonis, doesn't need to throw the towel. The big twist here is that Ivan of all people does, saving his son from a pointless beating.

How are the movies different?

"Creed II" does depart from "Rocky IV" in one big way.

The older movie, which takes place in the midst of the Cold War, is part personal, part political. Ivan, an avatar for Soviet evil, has zero redeeming qualities. The Soviets have trained him as a killing machine. There are menacing Russians and state minders to remind the viewing audience of how oppressive the government there can be. Apollo takes his fight partially out of a sense of patriotism, saying, "It's not just an exhibition fight. It's about us against them."

In "Creed II," there's no America versus Russians dynamic at play. Viktor was raised by his father, bitter and scorned after his wife and his countrymen abandoned him in the wake of his own defeat. The two live a pretty miserable existence. So while you fear Viktor Drago, you end up feeling kind of bad for him, too.

Oh, and one other difference? In "Rocky IV," there is a funky robot character. Why, we have no idea. Mercifully, there is no robot in "Creed II." (Unless you count Jordan's abs, which look like they were also manufactured in a workshop.)