16down. Marathon character in cartoon - invariably a cliffhanger? (4,6) r?a?, r???e?
27accross. 12d - as it used to be! (8) s???l???
24d/17d. Original addition to the Declaration of Independence (5,9) ???s? amendment
I did have fifth amendment as answer which means my 28accross is incorrect. The clue for 28accross is (8 letters) Brilliant, however silly it sounds I had the answer as stupendous?