The Fifth Dimension truly was a unique ride. It was designed in house originally by some big wigs at tussauds who had never designed an attraction before.
John Wardley and a handful of other Tussauds designers were brought in after its first year of operation as the park openly admitted the story was a failure. The original set pieces were huge but the story was very confusing and many people did not know what was happening on the ride nor what they were queuing for.
Prior to the 2nd year of operation, John Wardley and co. brought totally rewrote the show and introduced a new character, Zappomatic, who guided you through the TV universe where you met all sorts of weird and wonderful creatures as he attempted to fix his blaster to destroy the big bad zorg - along with the riders help of course.
It was a very unique ride. The legend (Dan I think?) over at British Theme Park Archive did an amazing documentary covering the ride (This is where I got my info from, well the stuff I could remember anyway!) but unfortunately he removed the video from YouTube.
British Theme Park Archive are truly an inspiration to the theme park industry, the work he has done documenting long lost attractions and interviewing the creative minds behind them is truly incredible - I do hope he returns some day!
I never rode the ride but I am sure others will be able to offer more info on the finer details of the attraction.