“The Voice” hit a season low, but good showings by “Chicago Med” and “Chicago Fire” helped NBC finish on top of CBS in key demos on Tuesday, a night that also saw a decent start for CW’s event series “Containment.”

Once again, cable news likely stole some potential viewers from the broadcast networks, with Fox News Channel (3.007 million), CNN (2.568 million) and MSNBC (1.712 million) combining for about 7.3 million viewers in preliminary primetime nationals from Nielsen. CNN was once again the demo leader among the networks (913,000), followed by FNC (600,000) and MSNBC (499,000).

On the broadcast side, according to preliminary national estimates from Nielsen, “The Voice” (1.8/7 in 18-49, 9.7 million viewers overall) tied for the 8 p.m. hour’s (and night’s) 18-49 lead with CBS’ “NCIS,” but the music competition series was down a full half ratings point from its prior Tuesday low this cycle. Looking better relative to past performances this season, “Chicago Med” (1.6/5 in 18-49, 8.1 million viewers overall) and “Chicago Fire” (1.7/6 in 18-49, 8.2 million viewers overall) grew 0.1 and 0.2, respectively, from their last originals of two weeks ago when the night kicked off with a “Voice” recap. “Fire” matched its highest rating since Feb. 8, winning its timeslot by a 55% margin over CBS’ “Limitless.”

At CW, “The Flash” (1.1/4 in 18-49, 3.0 million viewers overall) was back in original for the first time in four weeks, down 0.2 from its prior first-run episode. It was followed by the series premiere of “Containment” (0.6/2 in 18-49, 1.7 million viewers overall), which could retain only a little more than half of its demo lead-in. The viral-outbreak drama was in line with recent demo results for “iZombie” in the 9 o’clock hour while up nearly 500,000 in total viewers; in fact, this was the largest audience in the time period this season for the network.

CBS, which won the night in male demos and total viewers, opened with “NCIS” (1.8/7 in 18-49, 14.6 million viewers overall), which was the night’s No. 1 show in 18-49 (tie), 25-54 (2.9/9) and total viewers, but was at a season low; even with an expected round-up to 1.9 in the finals (it’s currently at 1.84), this would represent the first-ever sub-2 demo rating for the amazingly resilient show, now in its 13th season. Also for CBS, “NCIS: New Orleans” (1.6/5 in 18-49, 12.0 million viewers overall) exhibited strong retention of the original “NCIS,” down slightly from its prior original, while “Limitless” held steady at 10 (1.1/4 in 18-49, 5.8 million viewers overall) in its penultimate episode of the season.

ABC started off the night with a repeat “Fresh Off the Boat” (0.7/3 in 18-49, 3.1 million viewers overall), followed by an original “The Real O’Neals” (0.8/3 in 18-49, 3.0 million viewers overall); while hitting a low, “O’Neals” did match or build upon “Fresh” in all demos. “Marvel’s Agents of SHIELD” (0.9/3 in 18-49, 2.8 million viewers overall) was back down a tick after rising last week, and “Beyond the Tank” remains on the schedule with another 0.5 in the demo and 2.1 million total viewers.

Fox opened with an hour of “New Girl,” with its regular 8 p.m. half-hour average (0.9/3 in 18-49, 1.9 million viewers overall) matching a season low, while the 8:30 p.m. score (0.8/3 in 18-49, 1.7 million viewers overall) represented a slight timeslot upgrade over “Grandfathered” and tied with ABC’s “Real O’Neals.” “Brooklyn Nine-Nine” (0.9/3 in 18-49, 2.0 million viewers overall) held steady, as did “The Grinder” (0.6/2 in 18-49, 1.5 million viewers overall), which remains low but has held at the same rating for a sixth straight airing.