He later worked on Martians Go Home (1990) starring Randy Quaid.
At around this time he was approached to write the script to the film Gremlins 2: The New Batch (1990), which was directed by Joe Dante and produced by Michael Finnell.
Haas also had a small acting role in the film as one of the scientists.
[2] Haas would later work with Dante and Finnell again, writing the script for and appearing in the film Matinee (1993), also work with Dante again on developing a script titled Termite Terrace, based on Chuck Jones' start at Warner Brothers in the 1930s, the project ultimately never made it to the pre-production stages as Warner Bros. chose to make Space Jam instead.
[4] In 2022, he presented a new novel, Sunland, as twelve serialized episodes of The Last We Fake fiction podcast.