Horror Island (1941)

Bill Martin, is the proud owner of a small boulder of an island
off the coast of Florida called "Morgan's Island." It is a
deserted useless rock to Bill, but by pure chance he stumbles
across a treasure map pointing to his island. The map is
presented to him by a peg-legged old sailor, Tobias Clump, after
Bill and his friend "Stuff" Oliver saves the man from drowning.
Clump was pushed into the water by a "phantom," who got away with
part of the treasure map. Clump tells them that the map shows the
way to infamous buccaneer Sir Henry Morgan's twenty million
dollar treasure. Soon after this, Bill's cousin George offers to
buy the whole island for the amount of $20,000, but Bill isn't
willing to sell. Instead he brings the map to a reputed
cartographer named Jasper who claims that the map is fake—it's a
very well-made forgery. Letting go of the thought of the
legendary treasure, Bill instead thinks of making some money by
starting a "treasure hunt" cruise to his island, for fifty
dollars apiece. He involves Stuff in the plans and together they
start out for the island to plant a fake treasure for the
tourists to find. On their way they are involved in a traffic
accident, and by "accident" meet the posh Wendy Creighton and her
boy toy, Thurman Coldwater. Since Bill is a little short of money
he persuades Wendy to take his treasure cruise.


The phantom that stole part of the treasure map from Clump
reappears and warns Wendy and tells her that she will die if she
stays on. She doesn't take this seriously, but the phantom
appears once more, this time in her bedroom at night, and warns
her again. Everyone believes that someone is pretending to be the
ghost in an effort to scare them all off. A man in a cape kills
Rod in front of Arleen, but when she gets back to the rest of the
group the private investigator McGoon suspects her of being the
killer. Bill suspects Tobias, who is still missing, and a
"footprint" from a peg-leg is found near Rod's body. It turns out
there is big reward set for the dead gangster, "dead or alive".
Tobias reunites with the group and tells of a key he has found.
It is supposed to unlock a torture chamber in the castle, where
Sir Henry Morgan's treasure is hidden. The group enters the
chamber but finds only a single gold coin. As they return to the
castle's main hall there is a note on the table saying "nine
left". The cross-bow fires again, but misses Clump by an inch,
killing the phantom instead. It turns out the phantom was no
other than an old shipmate of Clump's. On the phantom's body they
find the rest of the treasure map.


Bill, Stuff and Clump go to find the treasure, leaving George and
Wendy to themselves in the castle. They find a new note saying
"eight left" and when George tries to find the anonymous killer,
Wendy is abducted by an unknown person. When the rest of the
group is back at the castle they find George murdered inside one
of the armor suits. Bill realizes that Jasper must be the killer,
but when Bill confronts him with Rod's gun in his hand, it turns
out the gun is unloaded and Jasper gets the advantage. Bill,
Stuff and Wendy escape, but only to find themselves trapped in a
secret passage inside the castle walls. As they get rescued by
Clump, it turns out the passage leads directly to Sir Henry
Morgan's treasure. Jasper follows and finds them, forcing them on
to the treasure chamber. As they open the final passage door an
axe falls down to kill Jasper. The rest of the group enter the
treasure chamber and opens the chest, only to find the skeleton
of Sir Henry Morgan himself. Disappointed the group members make
their way back to the surface, where they meet a government
agent, who offers to buy the whole island from Bill in order to
build a naval base. After all the mysteries are solved, Bill and
Wendy become a pair, making Bill worth $7,000,000.