Sci-fi screenwriter Bryant Moore filed suit against Cameron late last year, claiming the moviemaker based his highly-successful film on his scripts for two projects called "Aquatica" and "Descendants: The Pollination", reported TMZ online.
However, Cameron, 57, has now filed his own legal documents in a bid to have the case thrown out, saying "Avatar" plot and characters are completely different to Moore's projects.
Cameron has appealed the judge to dismiss Moore's lawsuit immediately.
