Steven Spielberg wisely junked most of the details from Zak Penn’s novel about a futuristic video-game and came up with a rather more eye-boggling set of conceits. Tye Sheridan plays Parzival, a young games who takes part in a virtual scavenger hunt for clues left by Halliday (Mark Rylance), a pioneering gamer who invented the OASIS, a shared virtual-reality universe for gamers where a series of breadcrumb clues have been left. Parzival’s real battle is with Sorrento (Ben Mendelsohn), who is keen to stop anyone else getting in control of this particular matrix. With many unreal concepts to deal with, Spielberg just about manages to make the convoluted drama of Ready Player One seem real; the best sequence is a trip to the Overlook Hotel from The Shining, which reduces the original to a ghost train ride, but still provides a genuine frisson. Cameos about, from the Back to The Future DeLorean to King Kong, and there’s always something going on visually to amuse. Unfortunately Rylance’s miscasting in a role that would have worked better with Gene Wilder robs the film of any genuine sentiment or warmth, but as a showcase for CGI, this is one hell of a toy-box mash-up.