She's also appeared in Gone Girl as Shawna Kelly, aka the crime scene groupie who offers to bake Nick a cake and won't delete that incriminating selfie!
Currently in the UK filming Ballot Monkeys on Channel 4, a satirical new comedy series about the general election, we asked Kathleen all about her new show, and what it's really like to work with Matt!
Hi Kathleen, so are you enjoying being in the UK?
"I refer to it as my second home! Since 2010 when I started Episodes, we've shot the majority of it here in London and the outskirts. I love it here; it's really a fantastic place to be!"
What's your favourite thing about being in London?
"The outdoor markets are my favourite! I was recently in Borough Market, it's so lively and amazing there, and the food is great as well! My favourite market of all time is the Columbia Road Flower Market. You guys do markets and parks like no other city in the world."
You've been filming Episodes for five years now, what's the funniest thing that's happened during filming?
"Well you can't get through a scene with Daisy Haggard, who plays Myra in Episodes! It's impossible to get through one take without laughing; the faces that she makes make her impossible to work with, but in the best way possible!"
Have you got any tactics to try and stop yourself laughing?
"I try and look at her forehead, but even her forehead is funny so it's kind of a stupid tactic! I try and not look her in the eyes because when that happens we just laugh hysterically. Well I do at least because she's making such a strange face! On that set it's always fun. There's not one diva in the bunch, Matt included! He's just a real normal guy who likes to fool around in between takes, be funny and prank people on set."
That's nice, Matt does come across like he's quite easygoing...
"Yes, exactly. Although in the four seasons that we've shot so far, we've only exchanged five lines as characters to each other, and those five lines ended in him telling me to f**k off! When we see each other on set we joke around by just looking at one another and saying, "You're in this?!", because we never ever work together. It's really funny. The writers tend to want to keep us apart, I have a sneaking suspicion, which I've told Matt, that they're afraid of the kind of magic we might have on screen together!"
Who was your favourite Friends character?
"Probably Pheobe, she's the one I relate to the most. But Joey was a strong contender, he's pretty loveable!"
How would you say you relate to Pheobe?
"I can be a little daffy and a little out there! I like how goofy she is. I make a lot of faces and do a lot of voices, so I think Pheobe and me would get along really well!"
Ballot Monkeys started in the UK two weeks ago, but for anyone who hasn't watched it, why should they?
"It's a very funny commentary on what's going on in the news. It's a bunch of really amazing actors being very funny, so why wouldn't you watch it?! I don't know a lot of what's going on, I'm going to be honest! A lot of it goes over my head, just because I'm a foreigner. I've still laughed a lot, and that's because of the great, funny, topical writing and a lovely comedic cast."
Parts of each episode are filmed on the same day the same episode airs. Is it nerve-wracking having such a quick turnaround?
"Yes, it's a very strange set-up and I've never experienced something like this. It is scary! The real stars of the series are definitely the writers, they're the ones under the most pressure. We show up on Tuesday and get scripts, and go on these buses, and they want us to memorise what we have to say pretty quickly. It's not easy shooting on a bus! It really has some very interesting challenges involved with it for everybody involved."
How would you describe the character you're playing?
"She's a feisty Texan and an American consultant for the Labour party, who hasn't done a lot of research! She shows up with a lot of advice that probably is a bit pushy and annoying to all of her fellow Labour party workers. She's annoying, but I think she means well!"
Will the final episode coincide with the election results?
"I don't know, I don't even know if the writers know! That's just the most exciting part about this! The main reason I wanted to take the job when it first came up was the idea of this kind of beast, shifting and moving and just changing, and we just kind of have to go along for the ride. It seems like such a huge challenge and also something that's incredibly fun and delightful and exciting to be part of!"
Ballot Monkeys airs on Tuesdays at 10pm on Channel 4.
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