In Vancouver, British Columbia, charter pilot and recovering alcoholic Vince Heldon and his wife Julie sadly place Vince's two young children, Don and Janet, on a commercial flight to return to their mother, Nora Stead. The children, who adore Vince and Julie, want to stay, but according to his custody agreement, Vince can only have the children six weeks a year. As Vince and Julie drive toward their lakefront home and business, the radio broadcasts a news report that the children's plane is on fire. They rush back to the airport, but after several hours, all contact with the plane has been lost. Although it is not yet daylight, Vince decides to take his seaplane out and search for the wreckage himself. Meanwhile, the children awaken near their plane, the only survivors of the mountainous crash. Don takes charge of the situation, gathering food and beverages from the plane and picking up a lighter and gun that belonged to a detective killed in the accident. Following the pre-crash words of the stewardess, Don tells Janet that they must stay near the plane, even though he knows that Vince's seaplane can only land on water. The next morning, an exhausted Vince flies home just as Nora, who is also a flier, arrives. Julie and Vince's partner, "Brandy," are wary of the aggressive Nora, who easily coerces Vince into resting instead of immediately going out again. At the crash site, when the children awaken, Don dismisses Janet's dream of seeing "a big pussycat," but when he then spots mountain lion tracks, he tells Janet that they must leave. Remembering that Vince had told him if you follow a stream it will always lead to a lake or river, Don takes Janet to a small lake. When she starts to cry from hunger, Don discovers that he left their only food at the plane and must return for it. Advising her to go wading in the lake up to her chest if she sees the "pussycat," he returns to the wreckage. A short time later, Janet sees the mountain lion and runs screaming into the icy water. While Don is at the crash site, he sees gasoline leaking from the fuel tank and decides to use the lighter to start a signal fire. The fire causes an explosion that incinerates the plane, but scares the mountain lion off. Back at the airport, Nora and Vince attend a briefing given by Wayne Langmuir of the transportation board. Langmuir believes strongly that they should not risk losing a plane to find one already lost and cautions that all rescue pilots must follow his plan. Although an Indian guide has reported the explosion and fire Don set, Langmuir dismisses it and wants the pilots to search a more likely area. Vince has a hunch that the explosion is the crash site, but Nora strongly disagrees. Vince finally convinces Langmuir to let him search that area by himself and takes off the next morning, accompanied by Julie. The fog is so dense that they cannot see anything on the ground, even though Don and Janet hear the plane and are sure that it is their father. While he is in the air, Nora learns that her own plane is going to be grounded for repairs. When the exhausted Vince returns, Nora goes to Langmuir and tells him that Vince has over-extended his flying time for the month. After checking the log, Langmuir grounds Vince, thus enabling Nora to take over his plane. When Vince again seems to acquiesce to Nora's wishes, Julie and Brandy are disgusted. While an embittered Vince goes off by himself, Julie goes to Nora's room and accuses her of deliberately sabotaging Vince for her own purposes and drags her out of bed to make Langmuir change his mind. When they find Vince, both Julie and Nora think that he has fallen off the wagon and Julie tells him that she will leave him if he goes back to drinking and self-pity. He is not drunk, though, and when he finds out what Nora has done, he determines to go looking for the children again after Nora convinces Langmuir. With Julie, Vince flies over his hunch area. When she spots the burned wreckage, he notices a nearby stream and follows it, knowing that Don would have looked for its source. Meanwhile, on the ground, the mountain lion has again started to stalk the children. Because Don had earlier emptied the gun to scare off the cat, they have no choice but to run and climb a tree. A few moments later, Vince sees the small lake and, with Julie's encouragement, makes the difficult landing. Just as the mountain lion is about to climb the tree and attack the children, Vince hears Janet's screams and runs toward them. He arrives in time to stop the lion and kill it with a large tree branch. Vince, Julie and the children are reunited just as Nora and Brandy fly overhead. Seeing the happy family, Nora breaks down and tells Brandy he has won: the children are safe and with the parents with whom they belong.