As "House" comes to and end (Mon., May 21, 8 p.m. ET on Fox), long-time star Jesse Spencer has been prepping for his next TV career as a firefighter. But Spencer, who starred on "House" for eight seasons, told The Huffington Post he didn't leave the set empty-handed.

"I took my pen," Spencer said on the red carpet for NBC's upfront presentation. "For eight years, I've been twirling and playing with that pen."

His other keepsake? His Dr. Robert Chase badge. "The badge -- the photo was from when I was 24, when I started the show -- so I wanted to keep that because I had long hair and looked about 12."

Spencer will next be seen in NBC's "Chicago Fire." The series, from "Law & Order" mastermind Dick Wolf, has been described as "ER" in a firehouse and follows the men and women of the Chicago fire department. After eight years on "House," Spencer said there was some hesitation about signing on for another series so soon.

"There was actually, I won't lie," Spencer said. "After coming off of eight years, which is quite a long time, I did think twice about it, but the script was great ... And it's the complete antithesis to what 'House' is. In terms of the show, 'House' was cerebral, clinical and very much a mind game show; this is a much more gritty, raw, emotional character-based show. We follow them into a lot of dangerous action situations."

For more on "Chicago Fire," click through the slideshow below and tune into the series finale of "House" on Monday, May 21 at 8 p.m. ET on Fox.

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  • Steve Pasquale, "Do No Harm," NBC

    "['Do No Harm'] is a medical thriller that's a reboot of the classic Jekyll and Hyde. If you like 'ER' and like 'Grimm,' that's a classic sort of cross-section of people that are going to love it."

  • Alana De La Garza (right), "Do No Harm," NBC

    "['Do No Harm'] is like 'Dexter' meets 'House,' that's how I always describe it because it's sexy and gritty and has the procedural medical part, but it's character-driven and inspiring and exciting."

  • Phylicia Rashad, "Do No Harm," NBC

    "The quality of the show. Absolutely the quality. I've waited a <em>long</em> time. A long, long, time."

  • Tracy Spiridakos, "Revolution," NBC

    "['Revolution'] is a post-apocalyptic show. It's quite the adventure, there's a lot of trekking around in the woods and discovering new things ... I would say it's for everybody because there's aspects of it that can be addressed to everybody."

  • Giancarlo Esposito, "Revolution," NBC

    "I am playing a villain, yes, a villain that has a little bit of a different flavor than any other villain I've played. The guy's probably been an accountant from Pacoima before he became Captain Neville of the militia. He's graceful, meddling and absolutely a lovely human being until he does something that shocks you."

  • '1600 Penn,' NBC

    <strong>The show is for fans of?</strong><br /> Jenna Elfman: "Well, he [Josh Gad] said it's "Modern Family" by way of "The West Wing." Did you tell him that?"<br /> Josh Gad: "Or ... 'Lost' by way of 'Damages.'"<br /> Bill Pullman: "It's being stranded in a very nice place, but with a lot of bad things potentially happening ..."<br /> Elfman: "And then there's a 'Dharma' factor."

  • Justin Kirk, "Animal Practice," NBC

    "I play a misanthropic veterinarian and there are funny people in it. I should say funny people, I don't know, I just show up with the monkey ... and then lots of animals. It feels like a ticking time bomb. I'm sure I'll be killed or maimed by some sort of snake or tiger."

  • Jenny McCarthy, "Surprise," NBC

    "'Surprise' is the show I want to be remembered by. It is inspirational. It's basically like 'Oprah's Big Give' meets 'CNN Heroes.' We take people that have done great things in their community and make their dreams come true. It's a real tear-jerker, it's emotional, but I also make it really funny and joke around with people."

  • Laz Alonso & Meagan Good (center), "Infamous," NBC

    Laz Alonso: "The show is about a very wealthy family doing very bad things. Meagan [Good] infiltrates the family to take them down."<br /> Meagan Good: "Yes, but what he didn't mention is that I actually grew up with this family when I was a kid and I haven't seen them in a couple of years. Also, me and Laz's character used to be former flames and haven't spoken in a while since he left San Francisco PD and became FBI. Now he comes in and recruits me so there's a lot of ... awkward tension."

  • Jesse Spencer, "Chicago Fire," NBC

    "It's an ensemble show -- we're going to get to know these characters very well as the show progresses. They drop things into the pilot, we get to see the situation where they are, what they're dealing with and then as we go along we're going to become more and more attached to them. When they are in life-threatening situations, you really feel like you're there along with them and you're really rooting for them. It's a great piece and I think we've got a great cast, really good writing and the show's going to have some legs."

  • Eamonn Walker, "Chicago Fire," NBC

    "'Chicago Fire' is -- it's going to be like 'ER' but in the firehouse. A wide variety and a very beautiful cast, but at the same time huge characters."

  • David Eigenberg, "Chicago Fire," NBC

    "[The firemen we trained with] said, 'You can do four hours, six hours, eight hours.' I said 'How long's a shift?' and they said, '24.' I said 'Can we do 24?' and they were like, 'Yeah.' So there we were bunking in the house. One house we went in, I said, 'Is this like we're doing a sleepover?' and they're like, 'Don't ever call this a sleepover ever again.' They were tough guys, good guys."

  • Connie Britton, "Nashville," ABC

    "Well, I did a lot of singing lessons, that was the most important thing. I watched a lot of videos -- a lot of Faith Hill, some Bonnie Raitt, although she usually plays the guitar, which, unfortunately, I am not capable of doing, Reba McEntire. Actually, country music hasn't been my background from the music standpoint, so I really needed to just immerse myself as much as I could, so that was it. And then spending as much time as I could at the Grand Ole Opry while we were in Nashville. That helped a lot."

  • Terry O'Quinn, "666 Park Avenue," ABC

    "[The role] seemed like it was well written, it was different. It looked like the character had a lot of levels to play -- nice and very not nice."

  • Janet Montgomery, "Made In Jersey," CBS

    <strong>On watching New Jersey reality shows for inspiration:</strong> <br /> "I have a lot of trashy friends that are really into reality TV, they were like 'OK, here's the rundown, you need to see 'Jerseylicious,' the 'Housewives of New Jersey' -- they're the most addictive things. They're total like -- nothing happens. Half of it you think that must be scripted because there's no way people are brawling in a pub right now. It's just so interesting. You can't stop watching, I love it."

  • Michael Urie, "Partners," CBS

    <strong>On playing characters based on the creators of "Partners":</strong><br /> "It was pretty cool -- I get to be Max Mutchnick, which is a lot of fun and it comes with a lot of inspiration. Both of those guys are so funny in life and their dynamic together is so ... they are joke writers extraordinaire and they make funny constantly."

  • David Krumholtz, "Partners," CBS

    <strong>On playing characters based on the creators of "Partners":</strong><br /> "It'll be interesting to mine their relationship further as the show goes further because they put on a show. They don't know it -- but maybe they do -- their working relationship is very out there for everyone to see and it's hilarious."

  • Lucy Liu, "Elementary," CBS

    <strong>On nervousness taking on the role of Watson: <br /></strong> "It's high risk and I think that that always makes you kind of stand up and think 'Oh gosh, should I get on the ledge or not?' Isn't life about risk? Especially our business of acting, you kind of have to take the leap."

  • Jonny Lee Miller, "Elementary," CBS

    <strong>On nervousness taking on the role of Sherlock: <br /></strong> "Yes, absolutely. It's like two sides to it: You're nervous because of that and then there's such a rich character and there's so much information that you can get from the books that helps you out so much ... I think there's a reason these stories keep being retold and redone because they're great characters. It's like Hamlet, or people wanting to play the Shakespearean parts a lot. Good stories come back and good characters come back. They're great characters to be able to play so that nervousness is the same as if you were doing Shakespeare."

  • Dennis Quaid, "Vegas," CBS

    <strong>On Ralph Lamb, the inspiration for "Vegas": <br /></strong> "He was a real guy. A fourth generation rancher who reluctantly became the sheriff of Las Vegas because of this big influx of ... planes were flying over his land, disturbing his cattle and the mob was coming in. A lot of the locals didn't like the way things turned out. I went out and met him in Las Vegas. He took me out to dinner to one of his old haunts with, actually, one of his old mob cohorts. They're good friends now."

  • Michael Chiklis, "Vegas," CBS

    "It's a fascinating backdrop for a television series. Las Vegas in 1960 and you've got real-life sheriff who reluctantly became the sheirff to sort of protect his interests as a rancher, played by Dennis [Quaid], a guy named Ralph Lamb."

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