Do not bother with a gift voucher as Vue do not accept it for on line bookings. I got one for my birthday from my grandson. I tried to book online for £5.99 a seat but they will not accept it, you have to go to the cinema and see if there are any seats available when you get there and if they say yes they charge you £6.99 because you did not book it online and that is your fault even though they will not let you use the voucher online.
