Operating on a return from a Maybe that contains "Just"

I have a function that has a return type of Maybe ([(Int,Int)],(Int,Int))

I would like to call this from another function and perform an operation on the data.

However, the return value is contained within Just. The second method takes ([(Int,Int)],(Int,Int)) and therefore will not accept Just ([(Int,Int)],(Int,Int)).

Is there a way I can trim the Just before applying the second method?

I don't fully understand the use of Just within Maybe - however, I have been told that the return type for the first Method must be Maybe.