To his great annoyance, Rodney wasn't the first one to notice that it was coming.
"Hey, Rodney." John was poking his head through the door of the lab where Rodney was being helpful and not at all bothering Zelenka at work.
"Yes! Rodney is here; please take him."
Rodney glared at Zelenka, then at John. "What?"
"The whales are being kind of weird."
That was enough to stop Rodney's nascent rant dead in its tracks. "Weird? How?" he asked, reaching out for them at the same time as he went up to John.
The whales were very happy to feel him. As one, they encouraged him to hurry, hurry or he would miss it...!
"Oh." Rodney said. "It's that time again." He grabbed John by the arm, and called Teyla and Ronon through the pendants.
"Come on! We don't have all night. East Pier, now!" On an afterthought, he turned around, and motioned to Zelenka. "You too!"
"But, Rodney, this work --"
"Can be done later. Now come! And bring popcorn." He directed that last to the pendant, since Ronon had rumbled something about being in the mess.
"Popcorn?" John was looking totally confused, and Rodney sighed impatiently
"There's no point in talking about it! The sun set half an hour ago - it should be starting already!"
He had been right. When they finally made it to the edge of the pier, the true darkness that should be settling in over the ocean was broken by a soft, mottled light that seemed to come from everywhere.
The whales were frolicking in it, great backs breaching the surface, diving and rolling, stirring up sparks of brighter colors.
"Wow," John said, taking an unconscious step closer to the water.
"Yeah," Rodney allowed. "It's not bad."
"What is it?" Zelenka asked, almost timid here away from his lab.
"The whales call it the Dancing Sea." Sort of. Rodney was being liberal in his translation of the concept of millions and millions of tiny organisms all spinning in intricate patterns, fighting against the currants to stay together in their preferred, perfectly organized strings and phalanxes and curtains, following mathematical rules so complex only the whales could fully comprehend them.
That's what transfixed the whales, and made them join in the motions when the minuscule specks of life came drifting by on their endless migration.
The drylanders could see none of that. On the surface, it was just light - but light that was growing brighter, as the phosphorescent microbes drifted upwards.
"Popcorn," Ronon said, and Rodney accepted the bowl while Ronon went to haul the tarp off the movie couch.
"Oh!" A soft exclamation of wonder heralded Teyla's arrival. Her face was all - glowy, and not just from the dancing colors. Rodney knew she had seen it before, but he had a vague feeling that he'd forgot to tell her the last time the migration happened. And maybe the one before that, too.
Rodney wasn't going to be able to resist the temptation of sliding in the shining water with his pod for much longer, but for now - just for now, he had a couch full of friends, and a bowl full of popcorn, and something to look at that was even cooler than a movie. Even cooler than Star Trek.
Sometimes, the dry wasn't so bad.