'Blue Bloods' Star Donnie Wahlberg
Actor Donnie Wahlberg arrives for the International Emmy Awards in New York November 19, 2012. Wahlberg stars as Danny Reagan in the CBS series "Blue Bloods." Reuters/Carlo Allegri

In “Blue Bloods” Season 6 episode 13,” both Detective Danny Reagan (Donnie Wahlberg) and Commissioner Frank Reagan (Tom Selleck) have a problem to deal with. Titled “ Flags of Our Fathers,” the episode will air on Dec. 11 on WGNAMER.

The District Attorney’s investigator Anthony Abetemarco (Steven R. Schirripa) will interrogate Danny over the accusation that his former partner planted evidence just to finish a homicide case. It is yet to be seen who the former partner is, as the top NYPD detective has had several partners.

In the pilot episode of “Blue Bloods,” Danny’s partner was Detective Demarcus King (Flex Alexander), who was replaced by Detective Ava Hotchkiss (Yvonna Kopacz Wright) and Detective First Grade Jackie Curatola (Jennifer Esposito) in the following episodes.

In “Blue Bloods” Season 3, Kate Lansing (Megan Ketch) and Candice McElroy (Megan Boone) became Danny's interim partners. It was Detective Maria Baez (Marisa Ramirez) who became his full-time partner.

On the other hand, radical anti-government activists threaten to burn an American flag publicly in “Blue Bloods” Season 6 episode 13.” Because of this, Frank truggles with the limits of free speech, Broadway World has learned.

Aired on Nov. 20, “Blue Bloods” Season 6 episode 9 titled “Hold Outs” saw Anthony Abetemarco (Steven R. Schirripa) helping ADA Erin Reagan-Boyle (Bridget Moynahan), who had to take a case from her colleague, ADA Kelly Blake (Diane Neal).

Aside from Danny, Frank and Erin, the other “Blue Bloods” Season 6 main characters are Officer Jamie Reagan (Will Estes), retired Commissioner Henry Reagan (Len Cariou), Linda Reagan-Boyle (Amy Carlson) and Nicky Reagan-Boyle (Sami Gayle). Detective Maria Baez (Marisa Ramirez) and Officer Eddie Janko (Vanessa Ray) are supporting characters.

Jamie Reagan’s superior officer Sgt. William Mulvey (A.J. Buckley) made his debut in “Blue Bloods” Season 6 episode 8 titled “Unsung Heroes.” Buckley starred in “Murder in the First” and voiced Pigeon Pete in “Teenage Mutant Ninja Turtles” before appearing in “Blue Bloods” Season 6.

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