Can I purchase a Merlin Annual Pass from Shrek's Adventure? Of course! Once you have decided which pass to go for, click here to purchase your passes. You can collect your Merlin Annual Passes from the Box Office on arrival. Related articles Can I pre-book my entry with a Merlin Pass? Why do I have to pay £1 to reserve my entry ticket? How long does it take to go around Shrek's Adventure London? What is Shrek's Adventure! London?