Corona's guards were first seen helping with the search for a magical flower that can help cure the ill Queen and save her unborn child. In which they subsided and brought back to the kingdom.
Eighteen years after the kidnapping of the princess, her crown became a reminder of her and the Guards were tasked to guard it, as it was kept in the throne room; however Flynn Rider and the Stabbington Brothers were able to steal the tiara from the men guarding it. The guards and their Captain gave chase and were able to capture the brothers while Flynn got away. They were later told that Flynn was at the Snuggly Duckling Pub and marched their way there; however the Pub Thugs helped the thief and his female companion escape through a hidden tunnel until the Captain's horse, Maximus uncovered the entrance. The Captain got one of his men to guard the Stabbingtons while they went after Flynn, but the brothers were able to over power the guard and escape. The other guards were able catch up with Flynn and Rapunzel and then were knocked out by the frying pan that Rapunzel gave to the thief.
There were some guards patrolling Corona when the thief and the birthday girl finally made it to their destination and had to hide from them a few times. Hours later, after the light from the floating lanterns were dying down, Flynn was sent to the castle with his and the crown that he stole tide to the helm of a small boat and the guards arrested him for his crimes; as well as the Stabbington Brothers. They then went to Flynn's cell so they could hang him for his crimes, Flynn had managed to over power them when he saw the Stabbingtons and got them to tell him how they knew of Rapunzel's hair, and when he got his answers the guards he knocked out got back on their feet and restrained him. The Pub Thugs however were able to help Flynn escape from the guards, so he could rush to Rapunzel's rescue.
When the Lost Princess finally returned home, Maximus became their new captain and got them to use frying pans; and to bring him apples.
Tangled the Series
The guards play a big part of the animated series, set 6 months after the film. In season 1, they are tasked by the king to watch the princess and protect her at all times. The guards are not featured in season 2 due to the gang exploring past the Corona walls. The guards play a very big part in season 3. After Cassandra invades Corona during Eugene's birthday, the guards step up to protect the kingdom and the Captain of the Guards decides to quit having this role after deciding he can't fight his daughter Cassandra in battle and gives Eugene the position as captain of the guards. Eugene is first seen as the captain in the penultimate episode of the series, with the guards assisting Eugene as their captain and the guards help the rest of Corona with the final battle against the villain, Zhan Tiri.