{{explanation}}
3s & 4s start on opp sides

1-8
: 1s & 4s set, cast in 1 place, 1/2 turn partners RH into prom hold facing
  each other & turn to right to end 1s facing 2M & 3s facing 3M
9-16
: 1s+4s dance 1/2 diagonal reel of 4 with 1st corners (end passing RSh to
  1s face 3L & 4s face 2L) & dance 1/2 diagonal reel of 4 with 2nd
  corners & end with Men dancing across to other Lady who turns right
  about into prom hold with other Man
17-24
: 1M+4L & 4M+1L (prom hold) repeat 1/2 reel of 4 with 2M/3M, then with
  3L/2L & end on sides facing partners in order 2 4 1 3
25-32
: 2s+4s also 1s+3s dance R&L