I had never heard of Paul & Rita Darrow before but look forward to reading more adventures. This one had everything - Lost World, Centre of the Earth, A Million Years BC, a cameo appearance from Son of Kong and blonde-haired fish maidens - always a favourite.
Poignantly, Paul Darrow (the actor who played the late, great, never to be repeated, Avon in Blake's Seven) died earlier this year. Were the two related? Probably not - but coincidences unnerve me.
The pages posted in the wrong order create an interesting post-modern effect - I pretended they were timeslips - but they could equally be life-affirming visions from characters under stress - Betty looked about to explode; scenes from a parallel world intruding into our own, or the effects of too much alcohol - your choice (or, if you are really really boring, you could just choose to read the pages in the correct order)
Link to the book:
Super Detective Library 050 - Lost Underworld