Douglas Fairbanks, Sr. went from being an actor known for doing light comedy to an action superstar when he made "The Mark of Zorro" (1920). It is the role he is still identified with today. As with most successes, a sequel was called for, and Fairbanks came out with "Don Q, Son of Zorro" (1925). Republic started using Johnston McCulley's famous character with "Zorro Rides Again" (1937). It was only natural that they would eventually get around to Don Q, but as always with Republic, some changes were made. Zorro was completely dropped, the main character was changed to female, and the setting was put into the modern era of the forties.
Dolores Quantaro (Adrian Booth), socialite and amatuer athelete, comes home to find hired thug Mel Donovan (Roy Barcroft) trashing her living room. He attacks her, but Dolores quickly mops the floor with Donovan, thanks to her expert knowledge of jiu jit su. Donovan gets away and Dolores calls the police about the attempted burglary. The first person to answer the call is enterprising reporter Cliff Roberts (Kirk Alyn). Dolores mistakes him for a policeman until the arrival of Inspector Grogan (Kernan Cripps) sets her straight. Going through the house, nothing seems to be missing
Donovan reports his failure to get the Quantaro family tree to his chief, antique dealer Carlos Manning (LeRoy Mason). Manning is displeased. He has in his possession an authentic land grant from the King of Spain to Don Quantaro that gives a large portion of California to the Quantaros. It is still valid. Manning is a distant relative and plans to collect on the grant. But he doesn't want any interfernce from any of the other relatives and needed to family tree so that he could track down and kill the other relatives, leaving him the sole heir.
Manning has Donovan hire a man to go to Dolores and pose as a historical author who is researching the old families of California. Dolores agrees to let the man see her family tree. He is taking down names when Cliff arrives to apologize to Dolores's Aunt Maria (Claire Meade) about his article on the break in upsetting her. Cliff recognizes the history writer as a known con man and a fight breaks out.
Donovan was waiting outside in case anything goes wrong. He quickly joins the fight. After accidentally shooting his own man, Donovan does manage to grab the family tree and get away. Dolores and Cliff discover a scrap of paper with some of the names from the diary on it.
When Donovan returns to Manning, he is instructed to start with some of the more distant relatives, and to make their deaths look like accidents. Some weeks later Dolores notices that three of the names on the scrap of paper from her family tree, have turned up in the obituaries. She goes to see Grogan, but he tells her that she has no evidence of any foul play. Cliff isn't so sure and decides to help her, while getting a story out of it.
They track down the last name on their short list and arrive in time to prevent Donovan from killing the man. Donovan tries to get away in a truck, but Dolores and Cliff give pursuit. Cliff manages to get aboard the truck, where he fights with Donovan. During the skuffle Donovan shoots another of his hired help, who was driving the truck. Donovan knocks Cliff out and then jumps to safety from the runaway vehicle.
Cliff comes to his senses and makes his own leap to safety right before the truck crashes into a power transformer and explodes. Dolores picks him up and they return to the man Donovan had attacked. They learn that he has a cousin who sells antiques, Carlos Manning. Cliff and Dolores go to warn Manning that someone is trying to kill all of the decendants of Don Quantaros. Manning feigns surprise at the news. Cliff postulates that it could be the work of someone on a personal vendetta against the family. This is all the cue Manning needs. He makes up a story on the spot about an ancient feud being documented in a history of the families.
After Cliff and Dolores depart, Manning formulates a new plan. Donovan kidnaps Dolores and tricks her into making a phone call to the police, telling where she is being held. Only the phone is a fake. Donovan records her and then calls Cliff, playing the recording. Cliff rushes over to the warehouse to rescue her.
Meantime Donovan has had the stuffing knocked out of him by Dolores. Eventually a net gets dropped on her and she is bound and gagged. Donovan and his latest assistant suspend her from the ceiling and rig a whale gun to shoot her when the door is opened, making it look like a ritual killing, and perpetuating the vendetta idea.
Cliff inadvertantly foils the plan. Finding the door knob squeaks and seeing Donovan through the key hole, Cliff doesn't want to alert Donovan to his presence. So he pops the knob out, which slacks the rope on it and saves Dolores, then swings the door open to get the drop on Donovan. Another fight breaks out and Donovan kills his third henchman (you would think he would have a hard time hiring replacements but they keep turning up through out the serial). The dying man falls against the whale gun, firing it. Luckily Cliff manages to grab a gun and shoot the rope Dolores is hanging from, which drops her to the floor, allowing the harpoon to pass over her head. Donovan escapes as usual.
Cliff manages to discover who Donovan is and through some underworld contacts learns that he likes to frequent the El Diablo Cafe for a knife throwing act. Dolores and Cliff visit the owner, and knife thrower, Romero (Jimmy Ames). He is unable to identify Donovan from a picture. Dolores comes up with the idea of replacing Romero's masked assistant in the act so that she can watch for Donovan and then signal Cliff so that he can follow the man.
The plan works and Cliff follws Donovan to Manning's shop. Thinking Donovan is about to kill Manning Cliff jumps the thug but Donovan manages to get out through a back door. Playing it cool, Manning thanks Cliff for saving his life and asks the reporter how he happened to be in the right place at the right time. Cliff tells about Dolores's posing as Romero's assistant, then says he has to get back to the paper and write up the story before picking up Dolores after the last show.
Manning imparts this information to Donovan, who returns to the cafe and clubs Romero into unconsciousness. Then puts on the man's costume and mask. He and Dolores go through the act until he gets to the final knife. Donovan plans to kill Dolores with it, and have the whole thing look like Romero did it by accident. Before the knife is thrown, Cliff arrives to catch the act and Romero stumbles out from the dressing area. Realizing the truth, Cliff jumps up onto the stage with a metal tray in his hands and puts it in front of Dolores. The thrown knife embeds itself in the tray instead of Dolores.
Donovan runs out the back and gets away. He reports another failure to Manning. His boss has even worse news. The delay in killing off all of his relatives and collecting on the land grant has nearly depleted Manning's funds. If they are to continue, they need money, and quickly. Manning starts to plan a series of robberies.
"Daughter of Don Q" is at first glance a typical serial from Republic in the mid-forties. The plot is an updated western, and slightly reminiscent of the Three Mesquiteers feature "Night Riders"
(1939), in which a riverboat gambler comes into possession of a Spanish land grant and poses as a nobleman to lay claim to a large section of Texas territory. The villains are neither flamboyant, nor do their plans involve any interesting science fiction devises.
That being said, "Daughter of Don Q" does have some interesting aspects for the serial connoiseur to savor. All of the fights are furious displays of destruction as directors Spencer Bennet and Fred Brannon reduce entire rooms to splinters. Plus the heroine is more actively involved with the fights than is usual. There are still scenes of her getting hit on the head so she can be put in jeopardy, but for the most part she gives as good as she gets, if not better. The concept of her being a master of jiu-jit-su is not just something tossed off in the first episode and dropped thereafter. There are many scenes of the stunt woman flipping and subduing opponents. It may or may not be real jiu-ji-su, I can't tell, but it looks impressive on the screen. I haven't seen this many henchmen get their hats handed to them by a heroine since "Zorro's Black Whip" (1944).
The acting is also something special. Mason and Barcroft give their usual and familar villainous performances, Mason seeming to be cultured, and Barcroft a not overly smart thug. Kirk Alyn is different. His take on the character is one who enthusiastically jumps into danger with a boyish grin. He is one of the most exuberant heroes to appear in a serial. It is totally unlike the serious performances he gave in his other Republic serials, even wisecracking occasionally.
This is well countered by Adrian Booth's more serious take on the murders happening around them. There are even a few scenes where her character gets visibly exasperated with Alyn's jocularity. A hero and heroine who do not get completely along with each other after the first chapter is practically unheard of in the genre. Booth also gets to garner the audience's sympathy by being allowed to show remorse and sorrow over being unable to prevent some of the murders of her character's relatives.
This also the first serial where a hero is shown to actually be engaged in his profession. Where some characters just seem to be able to arbitrarily drop whatever it is they do for a living to pursue a villain, Alyn's character actually has to take time out from tracking down clues to file copy at his newspaper. He also just doesn't happen to have a gun, something all Republic heroes keep on their person, even if they aren't involved in law enforcement. Chapter 1 has a scene where Alyn goes to the police department and gets a gun license. He is even warned about using it.
There are also in jokes for the fan. When Alyn and Booth are looking at a mug shot of Barcroft, his identifying number is 39013, the same as Charles Middleton's in "Daredevils of the Red Circle" (1939). All in all, "Daughter of Don Q" is a solid thriller.