Turning Off PlayerMovement Script when character isn't active?

I’m making an X-men Legends type rpg and I have a script where the camera switches to the selected character, the only problem is now all the characters move when I want to control just the selected character. I’m stumped can someone assist me with this?

  public GameObject[] characters;
  GameObject currentCharacter;
  int charactersIndex;

	void Start () {
	  charactersIndex = 0;
	  currentCharacter = characters[0];
	}
	
	void Update () {
	  if(Input.GetKeyDown("space"))
        charactersIndex++;
        if(charactersIndex == characters.Length){
          charactersIndex = 0;
        }
        GameObject.Find("Main Camera").GetComponent<CameraFollow>().target = characters[charactersIndex].transform;        
        currentCharacter = characters[charactersIndex];		
	}

If each player has a movement script then set it enabled = false before you switch to the next. You could also read about the concept of a PlayerController from Unreal Engine, which uses one input class that routes that input to any one character at any given time in the game: