Debby Ryan plays Lucy Diamond in ‘The Mysteries Of Laura’ Posted on March 3, 2016 by Los Angeles 1 Los Angeles Los Angeles News & Search 1 News - 1 eMovies - 1 eMusic - 1 eBooks - 1 Search Search for: She guest starred in The Mysteries of Laura last week and will return as Laura’s (Debra Messing) sister in the season finale on Wednesday. More: http://foxla.com/good-day/good-day-la-celebrity-interviews/99806633-story 1 Los Angeles Los Angeles News & Search 1 News - 1 eMovies - 1 eMusic - 1 eBooks - 1 Search Search for: