Two shows that were already producing extended seasons padding things out a bit more this week.

ABC ordered an additional episode of "Castle," while NBC ordered an additional episode of "Chicago Fire." Since both shows had already been extended to 23 episodes earlier in the year, both will now have 24 episodes this season. Do we hear 25?

Currently in its fifth season and nearing its 100th episode later this spring, "Castle" previously aired 24 episodes in its second and third seasons and 23 last season. The Monday drama remains a solid performer for ABC, though numbers have been down in recent weeks without the benefit of "Dancing with the Stars" as a lead-in.

NBC's "Chicago Fire," meanwhile, is in its first season and has been doing strong Wednesday 10 p.m. work, particularly by NBC's low standards. The Dick Wolf-produced series has been topping ABC's "Nashville" in live viewing.