Thirteen-year-old twins, Lettie and Will Dennis and cousin Jonas Wingate are unwilling visitors to an old Maine homestead threatened by the proposed construction of a new bridge. Their hostess, older cousin and village pharmacist, Mary Pete Tibbetts enlists the trio's efforts in a search for evidence to establish the old house as the site of a former Pilgrim trading post. Stowaway adventure, smuggling, possible poisoning, and a salvaged romance are credibly presented by the author who conveys depth of characterization through conversation and the incidental inclusion of Maine's human, herbal, and wildlife. Regard for natural beauty and historic landmarks is an intrinsic value in this mystery which combines a graceful style and absorbing action.