Can I send my query letters to agencies instead of specific agents?

[Joss]

You can't ask complete strangers if you can subvert an agency's guidelines. We're not the ones who are considering your query letter. You need to follow the guidelines posted on the agency website. If it says to send your manuscript to a specific agent then send it to a specific agent after you do some research on what they represent. How can you have trouble finding individual agents when most literary agencies (I've been to well over 100 websites, probably close to 200) and most of them have bios for all their agents. You can google the agent to see if s/he has a twitter feed, facebook, blog, website, or has done any interviews that you can read. And you can lookup the agent on publisher's marketplace to see if there's more info there, and sometimes an agency website might say to send your query to the agency, but an individual agent might tell you to query them specifically at their email.

The only way you'll have your work passed on if if the agent you queried thinks it's good enough to be published & thinks it's more to their colleague's liking. Many agencies do this if the manuscript warrants it. Since publishing has a high rejection rate, I can only imagine that most ms don't warrant this action.

And after I write all of this i see it's a screen play. Screen plays are definitely different; and never assume, always try to know for sure. I'm not sure how hollywood agents for screen plays handle it. You'll have to ask someone who knows. It helps to mention this upfront.