Story highlights Group of graffiti artists sneak subversive Arabic graffiti onto an episode of hit TV show "Homeland"

Phrases included "Homeland is racist" and "Homeland is a joke, and it didn't make us laugh"

Artist Heba Amin says: We "hacked" the show because we disagree with its political message

(CNN) Ask graffiti artists to help decorate the set of your TV show -- and you might get more than you bargained for.

That's how a group of street artists managed to sneak subversive Arabic slogans -- including an accusation of racism -- onto an episode of award-winning U.S. spy series "Homeland," which stars Claire Danes.

The graffiti, which included the phrases "Homeland is racist" and "Homeland is a joke, and it didn't make us laugh," made it into an episode which aired in the U.S. on 11 October and will go out in the UK this weekend.

Photos: 'Homeland is racist': Artists hide subversive graffiti in hit TV show Claire Danes star of hit U.S. TV series "Homeland" walks past graffiti on a wall that says in Arabic: "Homeland is NOT a series." Hide Caption 1 of 9 Photos: 'Homeland is racist': Artists hide subversive graffiti in hit TV show A group of artists asked to spray graffiti on the walls of a "Homeland" set to make it look more authentic sneaked derogatory slogans in. The graffiti here says, "Ready to die." Hide Caption 2 of 9 Photos: 'Homeland is racist': Artists hide subversive graffiti in hit TV show Danes as Carrie Mathison walking through a fictional Syrian refugee camp past the graffiti slogan: "Homeland is racist." Hide Caption 3 of 9 Photos: 'Homeland is racist': Artists hide subversive graffiti in hit TV show One of the artists, Heba Amin, says they did it because the show portrays world events inaccurately. The show launched in 2011 and has focused on Islamist extremism and terror in the Middle East. The larger graffiti slogan reads: "Homeland is racist." Hide Caption 4 of 9 Photos: 'Homeland is racist': Artists hide subversive graffiti in hit TV show The episode's make-believe refugee camp was set up in an old factory on the outskirts of Berlin. Graffiti reads "Homeland is NOT a series." Hide Caption 5 of 9 Photos: 'Homeland is racist': Artists hide subversive graffiti in hit TV show This slogan reads: "Freedom ... now in 3-D." The episode containing the artists' subversive slogans aired in the U.S. this week and will air in the UK at the weekend. Hide Caption 6 of 9 Photos: 'Homeland is racist': Artists hide subversive graffiti in hit TV show This one reads: "Homeland is a joke, and it didn't make us laugh." Critics have accused the series of bigotry, Islamophobia and of portraying Muslims in a crude way. The head of the company that makes the show defends its right to "tell difficult stories in difficult parts of the world." Hide Caption 7 of 9 Photos: 'Homeland is racist': Artists hide subversive graffiti in hit TV show Graffiti reads #blacklivesmatter, referencing the activist movement that sprang up in the U.S. in the wake of the 2013 acquittal of George Zimmerman of murdering African-American teen Trayvon Martin. Hide Caption 8 of 9 Photos: 'Homeland is racist': Artists hide subversive graffiti in hit TV show "Homeland is a sham" this graffiti reads. The literal translation of sham in this case is watermelon -- often used in Arabic to indicate something is not to be taken seriously. Hide Caption 9 of 9

In one scene, Danes, who plays bi-polar ex-CIA officer Carrie Mathison, strides past Arabic words sprayed on a wall that translate as "Homeland is NOT a series."

CNN has contacted Showtime, the makers of "Homeland," for comment but have not yet received a response.

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