open the thread.
replace the last bit in the address bar at the top of the page(in this case - welcome-to-clue-chain)with, offset/followed by a number.
to decide which number, every post has eg 'Post 134 of 139' in it's bottom left corner. put in one below the last number (138 here).
that takes you to the last post, if you then click on the last page number at the bottom it will open all of the last page.