void main()
{
    // Get the creature who triggered this event.
    object oPC = GetEnteringObject();

    // Only fire for (real) PCs.
    if ( !GetIsPC(oPC)  ||  GetIsDMPossessed(oPC) )
        return;

    // Only fire once.
    if ( GetLocalInt(GetModule(), "DO_ONCE__" + GetTag(OBJECT_SELF)) )
        return;
    SetLocalInt(GetModule(), "DO_ONCE__" + GetTag(OBJECT_SELF), TRUE);

    // Have the PC perform a sequence of actions.
    AssignCommand(oPC, ClearAllActions());

    // Have the PC say something.
    AssignCommand(oPC, SpeakString("Bare cells lie behind stout bars kissed with rust. The doors are open, but hardly inviting."));
}