The actor told Fancast that the series, which has been on a three-month hiatus, has "completely changed".
"One of the things that is really exciting is that, for a while, [the characters] were all in our little bubbles with our own storylines," he said. "Now it is all starting to converge."
Ritter added that he was surprised to be working with co-star Laura Innes (Sophia) in the new episodes.
"I am getting to work with actors that I haven't gotten to work with," he confirmed. "Laura Innes and I have a scene together coming up and I didn't think that would happen for a couple of seasons."
Ritter, who plays Sean Walker, previously teased that "huge secrets" will be revealed after the show's mid-season break.
The Event returns to NBC with a double-bill this Monday at 8/7c.