Robby the Robot

One of the most unexpected “guest stars” in Columbo isn’t an Oscar winner or a familiar character actor — it’s a seven-foot-tall chrome legend from 1950s science fiction. In Season 3’s Mind Over Mayhem, the Cybernetic Research Institute has its own household celebrity: MM7, a hulking, soft-spoken helper who can do “almost anything a man can do.” Look closely and you’ll recognize him immediately: that’s Robby the Robot, fresh out of Forbidden Planet lore.

How did Robby end up on Columbo?

Robby the Robot was built for MGM’s 1956 film Forbidden Planet, and he became such a recognizable prop that studios kept wheeling him back out whenever they needed instant futuristic credibility. By the time Columbo wandered into the Institute’s blinking control room, Robby had already cemented his status as a pop-culture sci‑fi icon — and Columbo simply rebrands him as “MM7.”

What does MM7 actually do in “Mind Over Mayhem”?

MM7 isn’t just set dressing. Dr. Marshall Cahill (José Ferrer) borrows the robot to help sell the perfect alibi: while Cahill is out committing his hit‑and‑run murder, MM7 is left behind to run the war-simulation controls and make it look like the doctor never left his post. Later, Columbo realizes the same thing Cahill does — if the robot can run the simulator, then Cahill’s airtight timeline suddenly has a very large, very metallic hole in it.

How did the robot work?

Robby isn't a robot in the way he pretends to be, as you probably suspect Robby is actually an actor in a suit. The suit was designed as three sections that lock together around the operator inside.

The robot looks like it drives around on wheels or tracks, but in fact the "legs" were designed in such a way that the actor inside can walk using short steps. It's not fast, but it doesn't need to be because Robby moves in a very slow deliberate way.

The arms of the suit are designed "bellows" style so the actor's arms can move as needed.

Some versions of the suit are powered (for the blinky lights and other little gizmos) via a power cable that comes up through one of the "feet". They hide it with camera angles and blocking it with other props or furniture, though in some cases the power was supplied by batteries in the suit.

Fun facts about Robby-as-MM7

• “Mind Over Mayhem” explicitly frames MM7 as a super-intelligent robot created by the boy genius Steven Spelberg.
  
  
• Columbo episode guides often call Robby/MM7 the episode’s most memorable ‘extra’ — and sometimes the only reason people rewatch it.
  
  
• Robby’s long résumé includes lots of TV appearances, and Columbo is officially on that list: “Mind Over Mayhem” (1974) as MM7.