Joss Sussman Glee star says he was swindled in Hollywood

"Glee" actor Josh Sussman says he was taken for nearly $30K ... when he tried to make a movie with a phantom production company.

Sussman claims in a lawsuit -- obtained by TMZ -- he made a deal with Mikel Dusi and Gold Rush Pictures to develop a feature film called, "Wally's Revenge" -- not realizing the company had been defunct for 2 years.  

The actor claims he forked over $30K to help development the project ... and says Dusi promised to return the dough within 90 days -- plus 20% -- after they got financing for the flick.

It's the oldest story in Hollywood.  Sussman claims not only is Dusi refusing to return the money, Dusi had the gall to demand another $50K if Sussman wants to buy out his interest.