Scarlett Johansson as Black Widow in Marvel’s “Captain America: Civil War.” (Film Frame/Marvel)

Last week, when I filed a rather cranky brief against the idea that a woman should play James Bond, an equally cranky reader wrote in to say I’d gotten it all wrong. A woman shouldn’t be Bond, he wrote, not because James Bond is a study in masculinity, but because men are stronger than women. Putting aside the silly and erroneous idea that general differences in biology means that every man on the planet is stronger than every woman, his email got me thinking about what makes for a good action sequence.

The emailer’s assumption seems to be that great action sequences are all about parity, that they’re a matter of equally strong people facing off against each other. But the true secret to a great action sequence is actually disparity, whether it’s a difference in styles, or a difference in strength and size that yields a surprising result due to the cleverness of one of the participants. Adding women to the equation introduces a new kind of disparity, and new opportunities for interesting fight choreography.

For two examples of fight scenes that are built around disparities, let’s return to the well from which this controversy sprung: James Bond movies. In the recent film “Spectre,” Daniel Craig’s James Bond finds himself facing off against Dave Bautista, who is a) a former professional mixed martial artist and professional wrestler, and b), giant:

The scene isn’t inherently fascinating. But it does do something mildly interesting in that it shows us a physically vulnerable James Bond. He’s not going to win by pure force, so he has to win by cleverness.

A much more interesting disparity comes early in “Casino Royale,” when Bond (also played by Craig) finds himself chasing a man (Sebastien Foucan) whose flight and fighting techniques are deeply informed by parkour.

The scene uses the difference between Bond’s style and his quarry’s to do a lot while saying very little. The target leaps down air shafts, bounds over tables and soars between construction cranes, while Bond tumbles over fences, lands hard on vent covers and commandeers construction equipment in service of his pursuit. Given that Craig’s tenure as Bond has come in movies that, at their best, examine the waning British empire and question whether the double-0 system functions well in a geopolitical environment defined by nonstate actors rather than great powers, the chase sets up that tension perfectly.

Now that we’ve got the basic idea down, let’s look at a couple of fight scenes where the disparity comes not just from size, or style, but from gender. In “Spy,” Paul Feig’s uproarious sendup of Bond-style espionage movies, Melissa McCarthy plays Susan Cooper, a mild-mannered CIA analyst who volunteers to go under cover when the field agent (Jude Law) she normally handles is killed in action. In this scene (which contains some mildly naughty language), Susan has to deal with her boss (Allison Janney), who has learned that Cooper is, in fact, a fighting machine:

Sadly, another scene where Cooper repeats this feat on a room full of men isn’t available online. But while both scenes are just as fantastical as Daniel Craig’s conquest of hordes of opponents, it’s worth taking a minute to look at how Feig and fight coordinator Walter Garcia lend McCarthy’s action scenes their own plausibility. Rather than treating her body size and type as a liability, they turn it into an asset. McCarthy can plausibly slam someone to the floor. And in another scene where she squares off against a murderous female agent with a knife, she is slow to retreat and blocks stabbing and slashing blows with heavy pots and pans.

In Marvel’s superhero movies, Black Widow (Scarlett Johansson and stunt double Heidi Moneymaker) has emerged as one of the most interesting characters to watch during fight scenes, not because she’s the same size and strength as other characters, but precisely because she isn’t. Fight coordinators such as Jonathan Eusebio and Sam Hargrave have developed a style for the character that’s based in her willingness to attack weak points and knock opponents off her center of gravity, and that relies on Black Widow’s dance training to give her grace and agility.

An early fight scene in “The Avengers” shows off the advantages of this approach:

The movie even stacks the deck a little bit by beginning with Black Widow tied to a chair. But once she gets started, she uses the chair legs to attack her opponents’ soft tissue and the sensitive small bones in their feet. She can get up faster than they can because she’s more agile, and she hits them both low and high, throwing them off balance.

Some of the same dynamics come into play in “Captain America: Civil War.” In an early chase scene in a Lagos marketplace, Black Widow uses parkour-like techniques to move more quickly over stalls and through stands. When she confronts the terrorists who have stolen a biological weapon, she grabs a soft basket to bat aside a gun and relies on her dancer’s ability to leap and fall carefully to catch the vial of the weapon. Sometimes, landing well is more important than landing the hardest punch.

Later in the film, when Black Widow and Sharon Carter (Emily Van Camp) are trying to slow down Bucky Barnes (Sebastian Stan), they use similar techniques, aiming for his head and groin, and using their whole bodies to keep a hold on them. In this context, Bucky’s mechanically enhanced strength and his brainwashed state make for a less-equal fight, but a less-menacing one.

Action sequences lose their zip when we see the same cities get destroyed over and over again, or when equally balanced opponents stage the same clashes for the zillionth time. Watching a woman compete, and get beat, in a compelling action sequence may not be girl-power fodder. But scenes like this one also remind us that something is at risk in an action movie; people can die and be something other than collateral damage in a glorious victory.

Adding women to the equation as worthy, if not exactly equal, participants can restore the excitement that’s so often been leeched away from contemporary action sequences. If they win battles against bigger, stronger men through cleverness and excellent technique, we get to see an underdog victorious. And if they lose, they remind us that all of this punching and kicking carries real risk.