At Castle Doom, Lotor announces that he's ready to wed Merla. It's a marriage of convenience, to merge Zarkon and Merla's two empires. The deal is sealed with a kiss. But Zarkon is unaware that Merla plans treachery - as soon as she takes Arus, she'll take his throne.
Her first act is to order the release of Roe, who goes home to his girlfriend on Arus. But of course, this wasn't done out of the kindness of Merla's heart. She appears to Taryn, the girlfriend, after the reunion, to ask a "favor". Taryn doesn't recognize Merla or Haggar, who is in disguise, and believes they are sincere. Merla claims to be in love with Keith but is too shy to give him a present. So she asks Taryn to help her out and deliver a corked bottle to him in time for his birthday party that night. Taryn gladly agrees, but Roe knows what they're up to and doesn't like it. However, he feels he has to keep his mouth shut or risk his freedom.
Taryn delivers the bottle to the Castle and gives it to Allura, explaining its origin and mistakenly thinking it's full of honey necter, not poison. Allura accepts the gift but is soon confused by her jealous feelings since some anonymous woman is showing affection for Keith.
Back at their little cottage, Roe's conscience gets the best of him and he tells Taryn everything. They vow to warn the others before it's too late. Haggar throws up some roadblocks for the brave duo, so they're delayed. Meanwhile, those at the Castle are ready for dinner but Keith is no where to be found. Pidge is impatient and wants to have some of the honey drink gifted to Keith. Lance, however, stops him from drinking it thinking they should wait for the guest of honor.
Keith, on his way back from picking flowers, stops by the couple's cabin only to find Lotor there. Lotor seems to be on a goodwill mission, though. He actually warns Keith about the poison for Allura's sake, as he's worried she'll be poisoned too. Not taking any chances, Keith strides off to warn them all. He manages to save the couple on the way, and would have arrived too late if not for the space mice spilling the drink on some flowers - the flowers withered cluing the team in.
Keith and Allura have a gushy scene where they're both spouting off their concern for one another. The flowers were for Allura. Awww. The scene was "pretty" sappy. Mercifully, all that's cut short when fighters fly by. They get the couple to the safety of the castle and launch those lions. The battle with the robeast was almost a challenge...until that blazing sword came out.
In the end, Lotor gloats to Merla about her failure and mocks their marriage. She suggests they call the whole thing off and tosses the bracelet given her during the ceremony.