Make object and everything behind it invisible

I want to make an object invivisble and that blocks vision for things behind it.
The purpose for this is for AR.
For example i want to place eyes that follow the user on a statue. When i am behind the statue i dont want the eyes to be visible through the statue.
I am quite new to shaders and wonder how this can be done.
Thank you for any advice or tips

 

You want a depth only shader.

Code (csharp):

1. Shader "Custom/Depth Only"
2. {
3.   SubShader {
4.     Pass {
5.       ColorMask 0
6.       ZWrite On
7.       Cull Off
8.       CGPROGRAM
9.       #pragma vertex vert
10.       #pragma fragment frag
11.       #include "UnityCG.cginc"
12.  
13.       float4 vert (float4 vertex : POSITION) : SV_POSITION { return UnityObjectToClipPos(vertex); }
14.       void frag() {}
15.       ENDCG
16.     }
17.   }
18. }

 

I hadnt had a chance to test it until to day. It worked somewhat.
It doesnt block everything. It seems to work while in scene but not when i build it to my phone.

In the picture there is a cube infront and behind the object with the shader.

 

NeverMind I got it working.
I changed the render queue and then it worked. (Pic) 1
How it looks (pic2)
Thank you very much for your help Bgolus.

 

Hey, I hope you guys might help me, Im using this shader, but in the build, Where it should be transparent Im seing all black, any ideas? Thanks in advance