A group of men go on an expedition seeking sunken treasure, and wind up battling bad weather, rough seas and each other.

In the 18th entry of Monogram's 24 "Range Buster" films, the bank of Gila Springs is robbed by Ace Alton and his gang, and Sheriff Frank Hammond, son of Marshal Jim Hammond, is killed. The Marshal sends for the Range Busters, Dusty King, Davy Sharpe and Alibi Terhune, to come and restore order to the town. Ed Cole, head of the local vigilantes, and secretly the head of the outlaws, promptly orders the trio out of town. They visit an old friend, Rancher Mike Rand and his daughter Mary. Mary's brother Jeff has unwittingly become a gang member, and carries out Cole's orders by taking a shot at Davy, but the latter makes him a prisoner during a subsequent fight in the town café. Jeff confesses to Cole's involvement, and the Range Busters, with the help of town banker Harrison, set a trap for Cole and his outlaw vigilantes.

Jim Steele spots Pete Dawson taking horses over the Mexico-Texas border, but Dawson has an alibi. A new group of recruits arrives at the Ranger station, among them Tex Wyatt, the son of Ranger Captain John Wyatt, whom he hasn't seen for many years. Captain Wyatt tells Tex that he is in the Rangers strictly on his own merit and there will be no favors played. He assigns Tex to pick up Dawson's trail, but orders that no arrest be made without proof.

Gold stages are being held up in the far west at a time when the U.S. government needs bullion, just before the famed "Black Friday" attempt to corner the gold market.

Dr. Herbert Lee, an archaeologist seeking to decipher ancient Mara inscriptions, is aided by his son Terry, Terry's pal Pat Ryan, and Normandie Drake. Jungle pirate and warlord Fang (Dick Curtis) plots to kill The Dragon Lady, Queen of the Temple of Mara, and seize the treasures of her ancestors. Both Fang and The Dragon Lady have sworn death for any foreign intruders.

In this entry in the long-running series of westerns, the Three Mesquiteers transform their ranch into a prison farm to provide a model for prison reform. They are opposed by a local contractor who wants to build a standard prison.

Someone is adding beef to Rocky Brown's herds and changing the brands to make it look like he is rustling. Then he is framed for murder and jailed. Johnny Argyle who has been sent to investigate believes he is innocent and sets out to prove it and starts with hides that have been rebranded.

The notorious outlaw Black Bart has reappeared and the Range Busters are sent to investigate. When they find that Black Bart is now a respectable citizen and that someone is impersonating him, they set a trap for the robber.

Red Ryder gets a telegram from his old friend Dan O'Connor asking for help in his fight against Faro Savage and his gang of rustlers. A gun dropped by Faro during a rustling raid makes Red and Sheila O'Connor, Dan's daughter, think they have ample proof against Faro but they are stymied by the law. Buckskin Blodgett and the Duchess, Red's aunt, find the body of O'Connor who was killed when Faro's men sent the sheriff out on a ruse. Sheila, discovered while rifling Faros office for evidence, escapes but not before she is recognized. Faro kills one of his own henchmen and then frames Sheila for the murder. Red and Little Beaver set out to clear Sheila and to try to find evidence against Faro and his gang. Written by Les Adams

Sergeant MacLane of the Mounties investigates the disruptive activities of a bunch of troublemakers.

A marshal is sent to clean up a mining town being terrorized by an organized gang that is killing miners and stealing their claims.

An elderly Catherine de Medici reflects back on how the prophecies of Nostradamus accurately predicted the fates of her husband, her three sons and herself.

A sea captain about to be hanged for a murder he didn't commit is rescued from the gallows by two of his crewmen. They head for the island of Pulinan, where they believe the real murderer--the captain's former partner--is hiding so the captain can clear his name. As it turns out, their troubles are only beginning

Sunset Carson is a wandering cavalier who rides into the Badlands. Hallie Wayne is bedeviled by bandits who've been raiding the livestock of her ranch.

When a fed-up businessman tires of watching gold shipments disappear without a trace, he calls in the Trail Blazers (Ken Maynard, Hoot Gibson and Bob Steele) -- a legendary trio of law enforcers -- to find the gold and figure out who's behind the thefts.

Hammond is after the Craig ranch and has framed Charlie Craig for murder. Mother Craig brings in the Range Busters. They capture one of Hammond's men and Alibi plans to trick him into a confession as to who the real murderer is. Meanwhile, Denny has overheard Hammond's plans for his next move and he and Crash set out to round up the gang.

Young radio personality Judy Joyner becomes mayor of the moribund town, Sleepy Lagoon, after running on an all women ticket and promptly sets out to turn the town around.

El Puma, a Mexican desert guide, escorts an archaeological expedition headed by Professor Lucius Lloyd through the Indian badlands of Mexico. Marian, the professor's niece accompanies the party as only she can translate the Aztec writings in the diary of her father, murdered on a similar expedition six years previous. The professor is murdered by a knife, and the weapon is recognized as the property of El Puma. Magpie, a Federal Investigator, knows that El Puma is really "Lightnin' Bill' Carson, a former federal agent who has been missing since Marian's father was slain. The reluctant Magpie believes that his old pal is guilty. Carson sets out to prove otherwise.

In his film debut Ritter is sent to investigate miners being killed and their mines confiscated. The culprit is Evans and after Tex joins the gang, he is sent to kill two more miners. When Estaban is killed, Tex is put on trial for all three murders.

A man has died leaving a fortune somewhere on his ranch. Brandon and his cohorts think a map is hidden in a picture frame. But when they bid on the picture at the auction, newcomer Jerry Lane outbids them. He also buys the ranch so they place their housekeeper there to get the picture. And then to keep Jerry out of the way, they frame him for murder.