Steven, Robbie and Amethyst were on the boardwalk, at the fry shop, asking for the bits. Exasperated, Mr Fryman grabbed three bags of the leftovers, "I'd have to throw them out anyway, my boys are tired of potatoes for a while" he  said handing them over. Robbie dig into his almost immediately, and Steven shared his with Amethyst, saving the last bag for the girls. They walked towards the beach house laughing until they noticed a glowing orb in the sky. Amethyst grabbed the boys, one in each arm and ran to the beach.

When they arrived, Bismuth and Spinel were staring at the orb, just as it turned into an eye. Steven asked "What is that thing?"
Bismuth replied "It's a Red eye, a recon drone. Garnet warned us of this. and that this is the last vision she saw, and the first.""
Sophie came out of the beach house, with Page trailing behind her, "That's right, I've been training with Mom's videos and I have a bit of a grasp on that part of my powers, she said her visions got fuzzy once I'd be able to See, and that's today. Don't worry, we got this. In her last message, did she mention anything we needed? I don't See today any earlier that that thing blowing up."
Bismuth explained about Rose's cannon, the only thing powerful enough to destroy the drone. All four kinds looked at each other and immediately agreed, they needed to find their dad.

At the carwash, they noticed that Greg was not in he office, so they all knocked and banged on the van to get his attention. It was only after Steven climbed the van and jumped on it, setting off the alarm, did Greg come out, disorientated as if he'd been sleeping. 
"Hey kids, what're you guys doing up so late?"
"It's only sunset Dad, we need your help" Page answered. "we need Momma Rose's cannon, Momma G said we needed it for that" and pointed at the Red Eye.
"Oh, I try to stay out of the gem side of things, but i think i know where that is. Climb in the van kids we have to go for a bit of a drive."

They ended up on the other side of town, at a storage facility. Greg lead them to a unit in particular, and opened it up. " This is where I keep things that don't really belong in the house, your mom's kept some stuff here too, if the cannon isn't in a magical gem place, it's in here. Schtoo-ball, Rocket, how about you guys try finding it. Me and the girls will try to find something out here to get it to the beach." The boys gave a half salute, before tying extension cords to themselves and diving into the unorganized mess.

Inside the storage locker, the boys found plenty of interesting things from Greg's past, plus a few odds and ends from their moms', like Garnet's keytar, a recipe book for pies belonging to Pearl, and a picture of Rose and Greg, that Steven accidentally stepped on. Greg forgave him immediately, saying "Don't worry about it kiddo, if every pork chop were perfect, we wouldn't have hot dogs". As soon as he finished the phrase a pink glow filled the empty space. Rose's cannon. The boys wrapped their cords around it and went outside to help pull the cannon out. The girls had found a wagon, but decided to make something out of a metal sled and a couple tricycles, it held better. They hooked it up to the van and they all hopped in and went as fast as they could to the beach. 

Once there, Bismuth, shocked, helped unload the cannon. Spinel praised the children for their quick thinking, and Greg for holding on to something so important to her friend. Amethyst was practical and pushed the cannon to the edge of the water and aimed it at the Red Eye. All they had to do was activate it. The children looked at each other, then at the gems, but nobody knew what to do. It was Robbie who remembered the light when his dad said his catchphrase. "Steven, say Dad's thing, it's your cannon now, it should work if you say it." Steven, blushing, did just that, and lined up on the beach with his siblings, Amethyst under the cannon, and the rest of their guardians behind them, the cannon went off, shooting a pink laser that bloomed out into a rose, then into Rose. The beam hit the Eye dead on and the machine exploded. Sophie had a tear fall from her good eye, as she wept in happiness.
"This is the moment Mom saw, the one that showed her we all needed to exist" she said, turning and hugging her twin. Page rested her arm on Steven's shoulder. Greg was the only one on the beach to notice the rubble falling on the town. He pointed it out to Bismuth, who broke the kids' bonding to tell them that tomorrow's training was going to involve cleaning up the boardwalk. Four simultaneous groans were heard as the family shuffled off into the house for supper and bed.