Y'all recognize that profile, don't you? The troublesome space trader was called Harry Mudd on the original Star Trek. On Space:1999 she was known as "the Taybor." In Star Trek: The Next Generation, the rogue space trader made trouble for Captain Picard in the dreadful second-season episode called "The Outrageous Okana."
Given the overall quality of these various episodes, you might hope (as I do...) that this character-type gets retired soon. And frankly, maybe that HAS happened. After all, there's not a rogue space trader on the new Battlestar Galactica, is there? When was the last time you spied one on TV?
Anyway, "My Favorite Marcia" finds stalwart Commander Gampu leading a team to study a star going supernova, when he determines that a "galactic distress beacon" has been activated on the fourth planet in a nearby star system. He investigates and finds that his old "friend," space trader Marcia Giddings -- a woman "with the happy faculty of always being in the wrong place at the wrong time" -- is hunting diamonds on the planet surface, but that her spaceship has been neutralized by an evil robot.
And that evil robot is -- wait for it -- a re-dressed Robby the Robot from Forbidden Planet (1956)! Yes, Robby has been given a new brain pan, a "dome" and glowing blue eyeball for Space Academy, and he's playing a "war machine" gone mad who Peepo says "wants to harm everybody." To prove his evil intentions, he traps Laura, Gampu, and Tee Gar in a yellow "force shield" (which is accompanied by the bionic sound effects from The Six Million Dollar Man and Bionic Woman).
Needless to say, there's a happy ending, as Peepo manages to short-circuit Robby. Oddly, the evil robot just vanishes into thin air without explanation. Don't quite understand how the little guy managed that. Anyway, I was disappointed that Gampu spends most of the episode sparring with Marcia rather than the evil robot. This seemed like the perfect opportunity to have star Jonathan Harris say something from his Lost in Space days like "You Bubble Brained Booby!" or the like.
Instead, we do find out here that Gampu's first name is Isaac. But we never find out what the robot was doing on that planet, or why he was attacking people...