Coming out of the Cineworld IMAX on London’s Leicester Square after the first UK showing of T2: Trainspotting, the critical mutterings are about ‘a nostalgia-fest’. But nostalgia isn’t always a dirty word. Whenever a group of old friends get together, there is always some reminiscing. It’s as natural as night follows day. It’d be impossible to attend a school reunion without talking about the past.