Bridge on the River Chozzerai
Allura was going to be taking part in a reinactment of that story, and had to choose someone to play the part of the man. Keith played it cool, so she had to choose between the others. Pidge offered to solve the dilemma by using a deck of cards - the one who draws the joker, wins. The lucky guy ends up being Hunk. The two head off to the bridge to partake in the ceremony.
On Doom, Lotor is plotting once again - most of his thoughts on making Princess his love slave than actually conquering Arus. He ends up destroying the center of the bridge before Allura and Hunk can meet there. Allura is trapped on a piece of the wrecked bridge, and Lotor leaps from his ship to grab her. Hunk intervenes while the rest of the team man their Lions and head that way. Hunk loses his footing, barely hanging on and when Lotor goes to step on his fingers, Allura tries to stop him. Lotor backhands her and she falls into the water below. Hunk tries to fend off Lotor's pursuit of the Princess by attacking his ship. However, Lotor strikes first and Hunk and his Lion are down for the count.
While the others deal with a Robeast, Lotor is waiting to intercept Allura at the Blue Lion. When threatening him with a pistol backfires, Allura turns one on herself. At the last moment, she turns the gun on Lotor. Though she misses him, the blast buys her enough time to board her Lion. Her concern is Hunk, who's still unconcious and underwater in his Lion. With the Yellow Lion damaged, Allura gives it a piggy back ride to the battle. She tosses it into formation so that they can form Voltron. I'm sure you know how the battle ends.
In the end, Yellow Lion is in for repairs and Lotor is chastised by his father.