Outside his cabin in northern Canada, a man catches an intruder and,
after killing him during a struggle over a knife, carries the body to
a deserted area and buries it. Later, Corporal Rod West of the
Northwest Mounted Police is about to leave on vacation when he is
summoned by Major James Robertson, who tells Rod about a letter from
Andrew McKay, head of the trading post in Healy's Crossing, who
reports that two men from the area have disappeared in the last few
Robertson then introduces Rod to Nancy Craig
(Anne Gwynne), whose father is
one of the missing men, and tells Rod that she will accompany him on
his investigation. After days of traveling by canoe, Rod and Nancy
have almost reached their destination when they are shot at by an
unseen assailant. When they arrive at the trading post, Andrew tells
them there is no one named Craig in the area, and arranges for Nancy
to stay at the home of Emily Mallory and her brother Paul, a miner
with an injured arm.
Andrew then tells Rod that he is suspicious of Mencheck, a bad-tempered miner who settled in Healy's Crossing several
months before. Rod questions Mencheck, and shortly after leaving his
cabin, Rod and his dog Chinook discover a body in a shallow grave.
Andrew identifies a cap found nearby as belonging to Blackie, one of
the missing men. Meanwhile, Nancy hears about Mencheck and,
recognizing his name, sets out to see him.
Finding Mencheck's cabin
empty, Nancy proceeds to search it and discovers her father's wallet
in a suitcase under the bed just as Mencheck returns. Nancy escapes
and goes to the trading post, where she tells her story to Andrew, his
friend Billy and Fred Foley, who works for Paul. The men go to
Mencheck's and try to capture him, but he shoots at them and wounds
Billy before Rod arrives and disperses them.
Mencheck tells Rod that
he and Craig came up together to mine for gold, but that Craig
disappeared the day they got to town. When Mencheck adds that Craig
was the only man who trusted him even though he is an ex-convict, Rod
apologizes to Mencheck for misjudging him. The next morning, Fred
tells Paul that they should get away before Rod discovers they have
dug a tunnel through to Mencheck's mine in order to steal his gold.
Paul chides Fred for missing when he shot at Rod in the canoe, and he
uses dynamite to rig a trap in the mine. When Rod arrives, Paul pushes
him into the mine and lights the fuse, and he and Fred run away before
the mine collapses, trapping Rod and Chinook and killing Luke, a
member of Paul's crew. Chinook escapes from the mine and fetches Mencheck, who rescues Rod and then admits that he killed Blackie, who
was one of Paul's gang, in self-defense when he caught him outside his
Back at the Mallory place, Paul divides the gold, keeping
Luke's share for himself despite Fred's protest that he should get
more because he killed Craig. Nancy comes in as Paul, Fred and Emily
are preparing to escape, and they take her hostage, but Rod and Mencheck rescue her and arrest the gang. As Rod prepares to depart
with his prisoners, he promises to keep in touch with Nancy, who is
staying behind as a partner in the mine.