Have seen a pack on ebay which says NOT FOR RESALE on the back.

Any idea what is inside ?

Well you made me look anyway. For packs not made for resale there seems to be enough people selling them.

What's inside? Cards. Based on a James Bond game, I guess. Packs are cheap and descriptions are pretty much the same, no cards showing. Looks like you have to buy to see the insides. I think that's the whole idea, which should be enough of a hint as to what you are really getting.

There are a few auctions which show the open packs and the cards inside.

Looks to be 4 cards, Bond, M, Q, and Moneypenny.

Plenty on ebay, as you said.