Nancy Drew: Trade Wind Danger

Synopsis:

San Francisco has tons to offer tourists like Bess, George, and me. Fresh crabs, cable cars, hikes -- and stalkers! Well, maybe stalkers! is a little harsh, but this older couple, Ed and Harriet, keeps popping up everywhere.
Coincidental or not, Ed and Harriet's appearances are smelling fishier than San Francisco Bay to me. So the investigation begins. But who knew it'd lead to more sleuthing -- in Hawaii?