The untold story behind the West's strangest legend!

Young Indian brave White Bull captures and tames a wild stallion and names him Tonka. But when White Bull's cruel cousin claims Tonka for his own and mistreats the horse, White Bull sets him free. Tonka finally finds a home with Capt. Keogh and the 7th Calvary, and in 1876, rides into the Battle of Little Big Horn with General Armstrong Custer, becoming its only survivor.