Laeta Kalogridis wrote a spec script about Joan of Arc titled In Nomine Dei. She sold the script to Warner Bros. in April 1994, but a film was not produced. Kalogridis has also been involved in writing the following planned films:
Laeta Kalogridis became involved as a peacemaker in the 2007–2008 Writers Guild of America strike, working with writers and producers to reach a solution. The New York Times reported her involvement, "Ms. Kalogridis and her friends... had become a pipeline to the guild members holding out for sizable gains, whose support would be needed if any deal was to be reached."