Fantastic Four withstood upset involving lasers initially (3,2,4,5)
I believe the answer is:
out of this world
'fantastic' is the definition.
(I've seen this before)
'four withstood upset involving lasers initially' is the wordplay.
'upset' indicates anagramming the letters.
'involving' indicates putting letters inside.
'initially' suggests taking the first letters.
The initial letter of 'lasers' is 'l'.
'four'+'withstood'='fourwithstood'
'fourwithstood' is an anagram of 'outofthisword'.
'outofthisword' going around 'l' is 'OUT OF THIS WORLD'.
(Other definitions for out of this world that I've seen before include "fantastic" , "Astronauts are sometimes" , "Late" , "good" , "Dead" .)