You need to sign-up as a member to get the deal. Membership is free and you also get a card that gets you $1 off non-discounted movies. After you sign-up, you need to login to the members area to print off the voucher which you take with you to the cinema.
just signed up, am logged in, but can't see any vouchers… is there a special url you need to have been emailed as an existing member to get the voucher?