Take a world-traveling uncle with a penchant for potions. Add his enthusiastic 11-year-old narrator nephew, absent parents, a few grumpy goblins, and miscellaneous quirky characters. Mix well. The result, like Duncan and his Uncle Dudley’s attempted adventures, doesn’t quite turn out as expected. Rather than being a fun read, Yourgrau’s story seems overstuffed with incident and oddly lacking in individuality. A disappearing spell gone wrong, two unrequited crushes (Duncan’s on his cello teacher, Dudley’s on a local waitress), the unintentional summoning of a pair of goblins, an abortive attempt to ride enormous bubbles across country, and a mishandled elixir of love are all crowded into a busy plot that drags just a bit. Characters and setting are too sketchily drawn to stir up much interest. Auth’s pen-and-ink illustrations help to ground the story in time (Duncan’s parents’ car has tail fins) and offer amusing glimpses of characters and events, but can’t compensate for the text’s lack of focus. An unsuccessful experiment by an author known to take chances in his titles for adults. (Fiction. 9-12)