How to make a transparent box as followed?

[29221-无标题.png|29221]

for example, the bucket in the picture. I wanna make the outer surface transparent and the inner surface visible.
Finally it looks like a wormhole in the space. I can see inner surface and the inside from above, but can’t see anything from below.
How can I do that in Unity?
Thank you so much if you guys can help me!!
Finally like this, I know I’m a terrible painter :smiley:
29222-3121.png

You can use this shader.

https://www.dropbox.com/s/kb3u91i7q43xg65/DiffuseWithFontCull.shader

let me know if you want different.