In this film Rin Tin Tin plays "Lobo", a wolf-dog half-breed and leader of a wolf pack. Lobo's wolf pack lives in the Sierra Nevada mountains, but wildfires force Lobo and the pack out of the mountains and into The Joshua Tree area of the California desert. (The movie was shot on land that later became part of Joshua Tree National Park.) Lobo and the pack have a habit of eating cows, and are thus a threat to the cattle ranchers of the area, who form a posse to kill them.
However, Lobo runs into Dave Weston (Charles Farrell) a good-hearted borax prospector who removes a thorn from Lobo's paw. Lobo soon becomes domesticated as Dave's dog. Meanwhile, Dave's borax claim is threatened by evil claim jumper William Horton, who wants Dave's borax and is willing to kill Dave to get it. Who saves the day? Lobo the dog, of course.
Rin Tin Tin was already a huge star, but Clash of the Wolves was a big break for Charles Farrell, who became a huge star of his own by 1927 and 7th Heaven.
- Action Prologue: The first shot of the movie shows a lovely Sierras waterfall—with a raging wildfire burning right next to the waterfall. This wildfire forces Lobo and the wolf pack to descend the eastern Sierras down to Joshua tree country.
- Amplified Animal Aptitude: Lobo often seems nearly sapient. He makes the tactical decision to separate away from the wolf pack to lure the wolf-killing posse after him, thus saving the rest. He is later clever enough to decoy the posse after him, thus leading them to his master, who is wounded and needs help. He is tasked with delivering a message from the hero to the hero's girlfriend, but when he sees the bad guy the desire for "revenge" overtakes him and he attacks the bad guy instead. For a while he trots around in some weird dog booties, but when he finds himself unable to ascend a slide, he is smart enough to rip the dog booties off, after which he makes it up a slide. He also knows how canteens work, as shown when he dips a canteen in a pond to fill it up, then brings it to his master to give him a drink.
- Babies Ever After: The ending has Dave and May going on an Old-Fashioned Rowboat Date with Lobo, Lobo's "mate", and Lobo's puppies, bringing up the rear in a tin pail.
- Because You Were Nice to Me: Lobo the wild wolf-dog has a thorn that he can't get out of his paw. He wanders off into the desert to die, but kindly Dave saves him. A title card then says that the "love" that led to wolves becoming domestic dogs thousands of years ago also leads to Lobo becoming Dave's pet.
- The Cavalry: Horton looks like he's going to get away, along with a kidnapped May, when Lobo howls for his pack, which comes down from the hills and chases after Horton and May. They save May, and Lobo kills Horton.
- Diabolus ex Machina: The only reason Lobo has to save Dave in the desert is that Dave stupidly drops his gun in the sand on the way to his claim.
- Establishing Character Moment: Horton is established in a title card as a claim jumper. That's bad! But the intense stare he delivers to May, in a close-up that also shows him creepily parting his lips, establishes him as evil in a completely different way. Sure enough, he gets rapey and tries to kidnap May at the end.
- Gory Discretion Shot: In the scene where Lobo kills Horton, they're hidden behind a bush.
- Have a Gay Old Time: May's father, who is not happy about her romance with Dave, demands of a flunky, "Have you ever seen this tenderfoot making love to my daughter?" Soon after he says "If I come back and find them making love—you're fired!"
- Heroic Dog: Rin Tin Tin, everybody. He jumps Weston on two separate occasions to save Dave from getting killed. When Dave gets shot in the desert, Lobo drags him into the shelter of a cave and later fetches him water from a canteen. When Weston is trying to get away with a kidnapped May, Lobo summons his wolf pack, which then attacks Weston, saving May.
- Made of Iron: Either this or Imperial Stormtrooper Marksmanship Academy. It's hard to say which. But here's what happens: Horton has shot Dave once and appears to finish him off. Lobo leaps from a nearby rock to save Dave. Lobo and Horton tussle. Horton breaks free, and fires his gun. Lobo flops to the ground. Horton fires at a stationary Lobo two more times at point-blank range. Horton flees on his horse. Then Lobo gets up like nothing happened, and pulls Dave into shelter in the cave.
- Mixed Ancestry: Lobo is specifically stated to be half wolf and half dog. He has the strength and fearlessness of a wolf but the loyalty of a dog.
- Old-Fashioned Rowboat Date: Ends with Dave and May going on a rowboat date with Lobo, Lobo's mate, and the puppies.
- Paper-Thin Disguise: Dave adopts Lobo as his pet. This is a problem, as the people of the town know Lobo by sight and want to kill him. What does Dave do? He puts a ridiculous fake beard on Lobo's chin. The string is clearly visible. Somehow, this works, and everyone is fooled.
- Prospector: A somewhat unusual example in that Dave is a young and handsome man, not a grizzled old coot, and he's prospecting for borax, not gold. Still, there's claim jumping involved.
- Race Lift: Rin Tin Tin, a purebred German Shepherd, plays a wolf-dog hybrid. He did this in a lot of his movies.