The plot of the story is that Supergirl is summoned to the villains lair to stop him from pulling trigger and setting off 4 Grenades filled with advanced nuclear technology ..but also doesn't realized that she has also walked into a trap. A 'Watery Trap!'. That's when things get interesting and she's ends up in the pool, struggling and drowning underwater due to a villain putting a kryptonite Necklace around her and she's struggling to keep her head above water. It's a parody to the Superman drowning scene in the Superman Movie made in 1978.