The surgical paralytic agents only works for 5 minutes, and must be continuously administered. Here Tubocurarine could be a good choice; with 5 min. onset and 30-60 min. effect. The Trailer for this movie describes the order of effect over 20 minutes...
Thanks BTW: Just in case anyone should wonder what tune is playing in the background when Sandy break her shoe 29 minutes in; Big Chief - One Born Every Minute. (Doc's Theme). v=2x0q4Kc9oEU