As "Sherlock" Season 4 gets closer, fans are getting new looks at the PBS series. The drama released a new behind-the-scenes video that shows the cast hard at work. While it doesn't contain any spoilers, it does reveal the scheduling problems facing the show. In the video, executive producer Mark Gatiss reveals that their very tight schedule forced the cast to read the scripts aloud in the evening. "Then we had the read throughs, all back to front, but it was the only way we could do it. Evening read throughs can be very tricky because, if you do them on a day when everyone has been working, they can be very flat. But everyone had come to it fresh, so it went extremely well."