If you are unable to resolve your case in the General Session's court, your case will go to the Grand Jury after being bound over after a preliminary hearing. A case can be directly presented to the Grand Jury bypassing an arrest warrant and General Session's court. A direct presentment is when the prosecutor goes directly to the Grand Jury through a "Sealed Indictment". A sealed indictment is often used in major drug conspiracy cases and sex crimes.
The Grand Jury consists of thirteen people who hear evidence and determine if you should be formally charged with a crime. It is a one-sided affair. You and your lawyer do not have the right to appear before the Grand Jury. The job of the grand jurors is not to determine guilt or innocence. Their job is to determine if there is probable cause that a crime has been committed.
There are no questions by your defense lawyer or a right to present evidence on your behalf. One other important detail is that if a General Session's judge dismisses for a lack of probable cause or failure to prosecute at the general session's level, the district attorney can present the case directly to the Grand Jury. This process is called a direct presentment.
If the Grand Jury determines there is probable cause, they return a true bill. This means you have been indicted and your case will be set for arraignment. If the Grand Jury returns a no true bill, the case against you is over unless the district attorney resubmits his case to a new Grand Jury and that Grand Jury indicts you.