Dancers start in two lines facing up.

          ⇐⇐   ⇐⇐  1  4  8  5 
Music    ⇓⇑
           ⇐⇐  ⇐⇐  2  3  7  6               
        

Dancers 1 & 2 move toward music and cross (passing right shoulders). When dancers 3 & 4 reach the same spot, they cross passing left shoulders. Continue in a grand right & left (twice around), ending up in home positions:

        2  4  6  8
Music
        1  3  5  7

(If dancers arrive home before the end of the music, twirl/spin in place.)