'Brooklyn Nine-Nine' season 4 spoilers news: Nine-Nine squad joins caroling competition; Jake and Charles goes toy hunting

Christmas bells are ringing in the "Nine-Nine" precinct for season 4 episode 10 of the police comedy TV series "Brooklyn Nine-Nine."

Titled "Captain Latvia," episode 10 of the show's fourth season will feature the team getting ready for a sing-off against another one of their rivals, the Metropolitan Transportation Authority (MTA), in a caroling competition.

This is not the first time that the Nine-Nine squad finds itself head-to-head against another team. As reported by Citizen Oracle, the squad has gone up against the Fire Department in season 1 and had a little bit of a feud with the Post Office in season 2. But as they have always done before when dealing with a nemesis, the squad will be giving all they've got to win the annual caroling competition and defeat the MTA caroling team.

In the previous episodes, it can be recalled that Charles and his partner Genevieve (Mary Lynn Rajskub) adopted a Latvian child named Nikolaj (Antonio Raul Corbo). In episode 10, Genevieve and Nikolaj are set to make another appearance.

According to the synopsis posted on TV Guide, Charles (Joe Lo Truglio) will also be enlisting help from Jake (Andy Samberg) to find his son's favorite toy for Christmas. However, in the midst of their toy hunt, the pair finds themselves facing off against a Latvian crime ring.

Jake and Charles has been one of the best tandems in the Nine-Nine squad when dealing with unprecedented situations on special occasions. It can be recalled that in Season 3, Jake was trying to look for a Christmas present for Charles and unintentionally ended up soliciting help from Charles himself. While in the shopping center, they encounter a robbery and hostage situation, similar to the premise of Jake's favorite action movie, "Die Hard."

"Brooklyn Nine-Nine" season 4 episode 10 is scheduled to air on Tuesday, Dec. 13, on Fox.