The Bobbsey Twins and the Cedar Camp Mystery #14 by Laura Lee Hope

"Beware Four-winged Blackbird," is the warning that introduces the Bobbsey twins to mystery in Canada where they search for a missing friend.

The Bobbsey twins travel north of the border for their latest adventure, in Ontario, Canada, where they solve the puzzle of the "Four-winged Blackbird."

What did Tommy Cheechoo, a Cree Indian living on Mr. Bobbsey's land, mean by his warning? When the Bobbseys arrive at Cedar Camp, they find Tommy missing. Hate the "Four-winged Blackbird" carried him away? With an Indian boy to guide them and a tame wolf to protect them, the Bobbsey twins search for Tommy Cheechoo. They find many strange things in the Canadian woods--a carved stone that looks like an evil spirit, fool's gold, and real gold--buried in sacks which have disappeared when the police come to check.

But before they go home, the Bobbseys not only manage to find Tommy but also discover the meaning of his message: "Beware Four-winged Blackbird!".