Ryan Byrne and Danial O’Brien, co-directors of The Book of Nightmares, assess production manager Hannah Craig’s scream during a break in auditions for their film at Ace Studios on Sunday. About 55 hopefuls, from youngsters to seniors, tried out for roles in the movie to be filmed this summer and fall. Some came in person. Others sent video submissions. Deadline for video auditions is May 20. Apply online at www.thebookofnightmaresfilm.com. Callbacks run May 28. “It’s been great,” said Byrne of public interest in available roles.