Andy and Lana Wachowski -- the masterminds behind "The Matrix" and the cruel bastards behind its sequels -- are now firing back against the screenwriter who said they stole his ideas for Matrixes 2 & 3 ... insisting the full trilogy was their OWN terrible idea and no one else's.
TMZ broke the story ... screenwriter Thomas Althouse -- famous for writing nothing so far -- filed a $300 million lawsuit against the Wachowskis, claiming they ripped off his screenplay "The Immortals" to write "The Matrix Reloaded" and "The Matrix Revolutions."
Althouse claims he submitted "The Immortals" to Warner Bros. in 1993 but never heard back -- then noticed glaring similarities between his movie and the Matrix sequels, like plugs in the back of characters' necks and robot-like "agents."
But the Wachowskis just filed legal docs denying his claims, insisting the entirety of both movies -- all the terrible dialogue, the random fight scenes, those ghost twins, and even the orgasm cake -- was their work and their work alone. A brave admission.
The Wachowskis want Althouse's lawsuit dismissed stat. They also want him to pay for their lawyers.
Calls to Althouse were not returned.