Page accessible only after redirect

[yasirbh]

Hello,

I am trying to create a landing page which asks for customer's email and once entered, they are redirected to a product page (created specifically for these users) which has a reduced price or whatever promotion I want to run, as an incentive. However, I want this product page to ONLY be accessible IF the user enters email. I don't want anyone to get to this product page any other way, even if they try to enter the URL manually. How do I accomplish this? Can I somehow set-up the product page in a manner that it requires password UNLESS redirected? 

I'm not sure how to proceed, so any help would be greatly appreciated.