What's wrong with my Enemy script?

I am completely stumped, very few times in programming have I said that but I can't seem to figure out how to get my enemy to flee away from my player! I am new to FSM's and AI behaviors so that might be why, but I get a null reference when this runs, not sure why. I just want a straight forward answer what I am doing wrong, and how I can solve it. I have been trying to figure this out for past couple days-week now.

 using UnityEngine;
 using System.Collections;
 
 public class FleeScript : MonoBehaviour {
     PlayerController PC;
     public int nextStateClicker;//change to private
     public float FleeTime;
     public GameObject target;
     public Transform thisTransform; //thisTransform
     public float minDistance = 10;
     public float runSpeed = 10;
 
     public float maxVel;
     // Use this for initialization
     void Start () 
     {
         Debug.Log ("Player has obtained coin, flee mode!");
         ChangeStateFlee ();
         PC = GameObject.FindGameObjectWithTag ("Player").GetComponent<PlayerController> ();
         maxVel = 28;
     }
 
     void Awake()
     {
         thisTransform = transform;
         thisTransform.position = new Vector3 (2, 0, 2);
     }
     // Update is called once per frame
     void Update () {
         
     }
 
     public enum FleeState
     {
         FSearch,
         FFlee,
     }
 
     public FleeState fleeState;
 
     IEnumerator FSearchState()
     {
         fleeState = FleeState.FFlee;
         yield return 0;
 
     }
 
     IEnumerator FFleeState()
     {
         /*Vector3 distance = targetTrans.position - transform.position;
         float updatesAhead = distance.magnitude / maxVel;
         Vector3 movePosition = target.transform.position + target.transform.rigidbody.velocity * updatesAhead;
         yield return (movePosition);*/
 
   

             if(Vector3.Distance(PC.GetTransform().position, thisTransform.position) < minDistance)
             {
                 Vector3 direction = thisTransform.position - PC.GetTransform ().position;
                 direction.Normalize();
                 thisTransform.position = Vector3.MoveTowards (thisTransform.position, direction * minDistance, Time.deltaTime * runSpeed);
             }
 
         yield return 0;
     }
 
     /*IEnumerator FleeTimer()
     {
 
     } Set Later */
 
     void ChangeStateFlee()
     {
         StartCoroutine(FSearchState ());
     }
 
     void ChangeStateSearch()
     {
         StartCoroutine(FFleeState());
     }
 }

Errors: NullReferenceExcetion get_position () and brings me to Vector3.Distance(PC... line