Mrs. Daisy Tower is 67, the widow of a former governor, and for the last year has undergone the untender attentions of her nephew Egleston and his overbearing wife Elfrida during her convalescence from pneumonia and a broken hip.
That might explain why she stows away in a laundry truck headed for Boston, but it doesn't really explain how she finds herself confronting a dead body aboard the private train of art collector Conrad Cassell, en route to the New York World's Fair.
She and her fellow passengers find themselves in a screwball comedy fix, set against the pageantry of the World's Fair opening day under the shadow of the Fair's spectacular trylon. Daisy must not only identify the corpse and the murderer, but save the Fair from destruction by a maniac-and find a way to get Egleston and Elfrida out of her hair.