Does anyone know of any credible literary agents in the Chicago area?

You're not looking for a literary agent. They represent books, not screenplays. Try ICM (http://www.icmtalent.com/). They are an entertainment agency that represents different areas of entertainment, including literary and Hollywood. I only know how to find their agents for the literary side. You'll have to figure out where to look for the agents that represent screenplays - it's not available on the site.

There are more agencies, but you'll have to look for them. Find some forums for screenwriters and you might find useful info in those places, maybe even a list of agencies that represent screenwriters.

My advice is to keep writing if this is your desired line of work. Writing one or two screenplays might not give you the experience you need to get an agent and get your work looked at by Hollywood. It's the same with writing novels. Writing one or two is nothing more than practice to hone your writing skill. Keep writing them and don't put all your eggs in one basket. It's possible that none of the scripts you've written is good enough, but maybe the 5th or 6th script is soemthing they'd want.

Lastly, you'll need to look outside the Chicago area. Most large agencies are not located in mid-America. They're located in places like New York City. All you need to do is find reputable agencies that specialize in your type of work. It doesn't matter where they're located because communication is easily handled by phone or email.

Good luck.

Literary Agents Chicago