They're fighting side-by-side when it happens. One of the boxes on the edge of the wharf explodes into red and white like a firework in the middle of the night sky. As one, they turn towards where the blast came from. Potter takes off running, making good on his name as the best Hitter the DMLE has ever seen and throwing multi-colored curses left and right as he sprints forward. Draco helps by shooting vipers and all other manner of snake to tangle with Harry's feet and watches as the snakes curl up Harry's slight frame to rest on his shoulders. They hiss at the furious crowd as it draws near and the crowd visibly hesitates. Draco smirks. This is exactly the kind of opportunity that they need.
With a twist of his wand, Draco sends the smugglers reeling like a bunch of bowling pins knocked off-balance as he forces the pavement to undulate like the waves on a beach. It's advanced spellwork, and Draco would be more proud of himself if he had a moment to spare. As it is, their window of opportunity was quickly starting to shrink, and unlike Harry, Draco wasn't indestructible. Already, the witches and wizards around Draco were surging to their feet just like he knew and dreaded they would, and he's down to his last resort.
Draco's last resort is an overpowered Protego. To a bird flying overhead, it probably looks like a shiny soap bubble swept up in an ocean of sooty darkly-colored robes, and Draco doesn't have the raw power to keep it sustained for long. Not like Harry would. This is why Harry and Draco were partners; they played to each other's strengths. Draco could stay at the back and yell at Harry to stop being idiot, and Harry could focus on what's right in front of him. The man had an excellent set of instincts.
Draco could use his videogame cheat-esque buffs to his heart's content, and Harry didn't have to worry about taking Draco's head off when he shoots something that should be classified as a WMD by the U.S. State Department. Sometimes, though, Draco has to wonder how these things came to be.
Draco's delicate little soap bubble is about to fall down on his head when he finally sees Harry's face in the darkness. He's running with something clutched in his hand. Success! The next thing he knows, Draco's being squeezed through a tube and dropped in their superior's office, who looks suitable unimpressed to see two of his best agents laying on the floor. Draco groans. He should've known. Harry was always impossible when it came to teleportation spells.