CBS is making a few adjustments on their fall lineup this year, particularly on two of its freshman dramas, Elementary and Vegas. Deadline reported that the network decided to up Elementary by two episodes, while at the same time cutting down one episode for Vegas.
Initially, both rookies were ordered a total of 22 episodes.
In summation, the modern Sherlock Holmes 'Elementary' is now airing its freshman season with 24 episodes while Dennis Quaid's Vegas, on the other hand, is now getting a full season of only 21 episodes.
Elementary is currently the network's best performer this season but the the procedural drama slipped down a bit. From the successful pilot airing of 3.1 rating with 13.41 million viewers, it plunged down to 2.2 rating, attracting less audience with 10.9 million last week. (source)