Goofs

When Nancy runs into the school, she knocks some papers off a desk. When the man pursuing her follows, the papers are back on the desk.

When Sam is at the boat dock, he goes into the shop and gets some thinner. As he is leaving the shop, he has the thinner in his left hand. When he confronts Cady, the thinner is gone. When he takes his daughter down the stairs, the thinner is never seen again.

When Nancy is being chased by whom she believes to be Max, she runs into a room filled with lockers. We see her right hand pressed up against a row of lockers and she is wearing a ring. In the very next frame, the ring is absent from her finger.

The launch in which the Bowden family travels to the houseboat has a full windshield. Later, when Sam leaves by himself, only the windshield's frame is present; the glass is gone.

When Cady is fighting off the three men hired by Bowden, one of the two men holding him simply disappears between the shot of Cady kicking the third man to the ground and the shot of the third man getting back up.

The house Nancy is hiding in has power for her 45 rpm record player, but uses kerosene lamps for lighting.

Animal sounds heard along the river when the private detective hands over the suitcase to Mrs Bowden are not those of the local fauna. One can distinctly hear the laughing voice of the kookaburra, a bird found only in Australia.