When longtime “Law & Order” fans discuss the show coming back for a historic 21st season, it’s impossible not to hear the anticipation in their voices. The same goes for star Sam Waterston, who will be back on the NBC procedural when the series returns Feb. 24 after more than a decade off the air. In fact, the man behind District Attorney Jack McCoy couldn’t help raising his voice in excitement when asked about setting foot on the famous set again.
“It was totally surreal. Unbelievable,” says Waterston, who appeared on nearly 400 episodes of the mothership series, from seasons 5 to 20. “It’s a step back in time. They built the 42 sets in every detail down to the books on the shelves to the linoleum on the floor. You know perfectly well that it wasn’t all being done for you, but you can’t escape the feeling that you’re being given this opportunity to step…
