Player Sanity Script

I am working on a script in C# that will track the players’ sanity. Up until now the script has been working however; now I am getting an error saying “unexpected symbol: ‘if’” I do not know what is going on.

Here is what I have;

using UnityEngine;
using System.Collections;

public class PlayerSanity : MonoBehaviour
{
	public GameObject player;
	public int insanityLevel = 0;
	public int maxInsanityLevel = 50;
	public int creatures = 0;
	public bool insane = false;

	void Start ()
	{
		//sanityArea = player.GetComponent<SphereCollider>();
	}

	bool isInsane()
	{
		bool ret = false

		if (creatures != 0) 
		{
			if (insanityLevel > 0 && insanityLevel < maxInsanityLevel) 
			{
				insanityLevel++;
				ret = true;
			}
		}

		return ret;
	}

	void Update ()
	{
		bool insane = isInsane();

		if (insane == true) 
		{
			print ("Player is insane!");
		} 
		else 
		{
			print ("Player is not insane!");
		}
	}
		
}

The error is pointing to line 21.

; missing in line 19

     bool ret = false;