Aquaman Episode 33 - "The Stickmen of Stygia" by Oscar Bensol
This episode opens with Aqualad and Mera preparing to play a practical joke on Aquaman. It involves putting together a fake spaceship that looks like it has crashed on the sea floor. Aqualad then sends out a distress signal to Aquaman, who heads out post-haste.
Unbeknownst to all of them, some aliens from the planet Stygia are keeping an eye (a big one) on all of them. Aquaman gets closer to the source of the signal, only to figure out pretty quickly this is a gag. Unfortunately, the whole thing goes wrong when a boulder Aqualad wedges loose tumbles out of control, and heads for Mera!
Aquaman throws himself in the way, getting knocked for a loop. He then chastises the two of them, only to watch Aqualad get blasted by the Stygian's immobilizer ray!
Aquaman gets hit with it too, but manages to escape the beam with the help of some finny friends. He then destroys the "eye cannon" the ray was emitting from, only to find himself dodging torpedoes fired from the aliens' ship. They carry knockout gas, and one of them finds Mera, rendering her unconscious. Some of Stygians come out of their ship and begin firing at Aquaman's finny friends, making the Sea King realize a different plan is needed.
Aquaman pretends to surrender, only to threaten the Stygians with a "reverse force ray", which seems to come from the fake wrecked ship that Mera and Aqualad had put together. Using the same gag on the Stygians that was attempted on him, Aquaman gets the aliens to give up and head home, leaving him, Aqualad, and Mera to have a good laugh. The End!
At no point in this series is it ever suggested that Mera is Aquaman's wife, or girlfriend, and here it seems that she's not even his contemporary: in fact, she acts more like a sidekick ala Aqualad. Although I did find it interesting that when the practical joke goes on, it's really on Aqualad who gets a scolding. Arthur couldn't help play favorites...
I love the shots via the Stygians' POV. They're very 1960s.