Toph (left, voiced by Philece Stampler) returned to help Opal (right, voiced by Alyson Stoner) rescue the Beifong family in episode 10 of "The Legend of Korra" Book 4. Nick

Bolin (P.J. Byrne) didn't have much luck winning back Opal’s (Alyson Stoner) affection in the last episode of “The Legend of Korra” Book 4. But he did join her and Lin (Mindy Sterling) at the end of the episode to go on a secret mission to rescue Su (Anne Heche) and the Beifong family from Kuvira (Zelda Williams). That mission was the focus of episode 10, “Operation Beifong,” released on Nick.com Friday.

Check out three reveals from episode 10 of “The Legend of Korra” Season 4:

Guess Who’s Back: The episode picked up with Bolin, Opal and Lin as they approached the work camp where Kuvira was holding the Beifong family. As they neared the camp the rescue party was crashed by a familiar face, Toph (Philece Stampler), who had emerged from her swamp home to help recuse daughter Su. Bolin was ecstatic to meet the legendary Toph, considering her his hero, but Lin was not as pleased. She had some unresolved issues with her mother stemming from her father's absence when she was growing up. However, the group managed to work together to infiltrate Kuvira’s camp and, with a little acrobatics from Lin, save Su and her family while most of Kuvira’s soldiers were watching the debut of her spirit ray weapon.

Spirit Problems: In Republic City, President Raiko (Spencer Garrett) was worried about a Kuvira attack. Prince Wu (Sunil Malhotra) suggested evacuating the civilians of the city, impressing Mako (David Faustino) until he realized Wu was only acting more responsible to try to win Korra’s (Janet Varney) attention.

Speaking of Korra, Raiko tried to get her and Varrick (John Michael Higgins) to create their own spirit ray weapon to counter Kuvira’s, but they would not after what happened with the agitated spirit vines in the last episode. Korra did, however, meditate into the spirit world to convince the spirits, who were fleeing the city, to help defend the city. They refused, though, saying helping Korra fight Kuvira would be no different than Kuvira’s spirit weapon.

Operation Zhu Li

Lin, Toph and Bolin may have freed Su and her family, but before they could all leave Kuvira’s camp, Opal noticed another problem. Zhu Li (Stephanie Sheh), Varrick’ former assistant who had been pretending to be loyal to Kuvira, had been caught sabotaging the spirit ray gun at the weapon testing. Kuvira planned to tie her up in the model city they were destroying to test the gun. Opal and Bolin went to save her and were soon followed by Lin and Su, who realized this was an opportunity to deal a blow to Kuvira. Toph decided to stay behind.

Bolin and Opal were able to rescue Zhu Li in time, but the whole group got caught in a battle with Kuvira and her soldiers, including a particularly entertaining showdown between Su and Kuvira. When Kuvira’s soldiers surrounded the rescue party, Toph showed up to save the day, taking out a few soldiers and getting her family, plus Bolin and Zhu Li, out safely while an angry Kuvira looked on.

Celebrating their successful mission, it appeared that Bolin and Opal had made up and Lin had made peace with her mother, but Zhu Li had some bad news: Kuvira was planning an attack on Republic City in two weeks!

What did you think of “Operation Beifong”? Tweet your thoughts to @Ja9GarofaloTV.