“All That Glisters” is episode nine of season two of Space: 1999.
Eagle 4 with Commander Koenig, Dr Russell, Alan, Tony, Maya and a geologist called Dave who is flirting with Maya to Tony’s annoyance are heading to a small planet where milganite, a rare mineral vital to Alpha’s life support, has been detected. Maya has detected the milganite as well as a lifeform, minimal readings and unidentified. The atmosphere is breathable. The commander, who should know better, says nothing down there will give them trouble. And there’s a glowing rock in a cave.
The Eagle lands and there’s three hours before Alpha is out of range – and most of the senior staff are on the Eagle! – so Koenig orders minimum power. Tony and Dr Russell remain in the Eagle as the other four head out. They find a cave with the glowing rock from earlier in it; Dave is excited. Until he scans it. It isn’t milganite. He doesn’t know what it is. But there must be a source of energy somewhere to power the glow. Dave wants to get a sample, but Koenig asks him to check for radiation and dangerous elements first. There aren’t any and Dave shoots a sample off. Which causes a strange fluid to ooze from the hole.
On the Eagle, they aren’t getting anywhere analysing the rock. Then Tony gets hit by a glow as he looks in the microscope. The doctor checks and says he’s dead.
However, it seems that only his heart has stopped. Which might be the definition of dead, but everything else, including his brain, is still working. The commander wants to get rid of the rock btu Maya says it might have the answer for Tony. He wants to head back to Alpha, but Dr Russell says the answers are here. Dave is heading out. He can’t do their job but he can do his. Alan goes with.
Dave and Alan are scanning the rock when the commander and Maya arrive. No milganite. Dave checked the area before choosing it to land. He wants to examine the rock fluid and, with reluctance, the commander agrees. It seems the rock is alive. Probably the lifeform they picked up.
On the Eagle, Tony gets up and there’s a glow around his head. He leaves the Eagle and Dr Russell tells the others. She thinks the rock is controlling Tony. The commander tells her to stay where she is as it’s safe there. Sure it is, with a human-controlling dangerous rock. The others go and look for Tony, who goes back to the rock when they leave and shoots another piece off which he collects before leaving. Maya notices and Tony returns to the Eagle, placing the second rock next to the first before lying back down. The two rocks merge.
The commander wants to head back to Alpha, but the controls are dead and they don’t have communications. They do have a rock that can change colours and is potentially dangerous. It seems to be intelligent, alive and with a purpose. They just don’t know what that purpose is.