People are having a good time in the dark.
It is dark
"it is dark" is synonymous with "in the dark".
exists e1 s1 x1 x2 x3.(n_dark(x3) & Theme(e1,x2) & Actor(e1,x1) & v_have(e1) & in(x2,x3) & n_time(x2) & a_good(s1) & Theme(s1,x2) & n_people(x1))
exists s1 x1.(n_thing(x1) & Theme(s1,x1) & a_dark(s1))