Night: Mark brings Dan, Fitzhugh, and Steve to an ophthalmologist lab in a crummy area of the town (Dan wonders why he set up shop here). He has checked it out and knows there are lenses inside which they can use on the spaceship. Steve uses the razor hatchet to spark out the electric wiring. A giant doberman shows up and Steve shoots sparks at it with the wire while the others run inside the drain. Steve jumps in where Fitzhugh, after a hysterical outburst, falls asleep in the drain while on lookout. Murtrah, the unstable optometrist (or opthalmologist), comes back in and puts on scientific lit up glasses-binoculars which allow him to see in the dark. He bends down and looks right at them, "Kalar told you I could not see in the dark."


When the binoculars fail for a moment, the three escape. Steve awakens Fitzhugh, "You fell asleep, didn't you?" The binoculars keep going on and off. The four hide behind a Keep Off the Grass sign in the park they came through. They throw rocks at Murtrah to keep him from adjusting or fixing the binocular-glasses and he drops them. The men bring the glasses back to camp. Mark figures the device works on an infra red principal--combined with a sealed liquid and the lenses inside. The liquid can convert to a gas sensitive to infra red rays. Fitzhugh is glad they got away from that madman. Steve wants to go back to destroy the other two pairs of binoculars. The four return, mistakenly thinking the lights are still out--the giant has a backup generator ("There are more ways than one to supply electric power"). Dan and Steve are up on a stool and the table top. Steve goes to a file box when the giant shows up. Steve jumps onto a lens cleaner spray top, spraying the giant long enough in the face for Dan to escape. Mark and Fitzhugh pull Dan away--he wants to go back and help Steve. Murtrah chains a clock chain to Steve's leg, then nails the chain into the table.


Murtrah believes Steve and company work for a Professor Kalar, who has access to captured Earth people through his friends in government. Kalar and the Academy of Sciences forced Murtrah out of the academy after he told them about his seeing in the dark. Murtrah believes if he had a grant, the glasses would be perfected by now. Steve refuses to tell him where the others are. With the doberman and the glasses, Murtrah tracks Dan, Mark, and Fitzhugh--who wanted to return to the ship to devise a plan to help Steve. Fitzhugh gets caught on a bush and is captured. Dan and Mark hide in a gopher hole---Fitz's yell drew the dog away from it. Dan scolds the girls and Barry for coming to the area to help. Dan tells Barry they will try to rescue the captain and Mr. Fitzhugh. After the three go, Mark tells Dan he is not optimistic. Fitz insults the mad Murtrah, telling Steve, "I am sick and tired of taking it easy! I won't be bullied any longer!" Steve diverts the giant's attention away from murdering Fitzhugh with the dog by telling the giant he saw Earth through the binoculars---which go out again. The giant doesn't believe him and threatens to let Romellan, the dog, loose on them if they don't show him Earth through the binoculars.


Steve convinces Murtrah to add something to the glasses and when the giant does go into a storeroom for liquid, Steve whispers to Fitzhugh, gives him a note and tells him to give it to Dan. Steve tells Murtrah that Mark can fix the glasses if he lets Fitzhugh go and get Mark. Murtrah agrees but will kill Steve if Mark doesn't show up. The note tells Dan that the giant and his lab must be destroyed for the safety of their group and all mankind. Steve ordered that everything in the lab must be blown up. Betty asks, "I--Uh, everything in it?" Barry realizes, "Not Capt. Burton, too?" Dan says, "Everything in it." Mark refuses to obey those orders and tells Dan this. Dan tells Mark, "I know Steve a long time and he doesn't write notes like this to be melodramatic." He figures unless there is some way to free Steve without killing the rest of them---that's the way Steve wants it. They get together rabbit meat they have to draw the dog off. Mark throws the mean and lures the dog away from the house; Dan, falling once or twice from the pull of the leash, manages to tie it to a fire hydrant. This allows Fitzhugh to get inside the vent with a homemade bomb device made with flares and other material from the ship. It has a 15 second fuse landing flare. Fitzhugh and Mark watch as Murtrah, using pliers, tortures Steve. Dan cannot watch. Mark decides to show up at the front door, hoping to get Murtrah distracted long enough for Fitz and Dan to lock the store room door--which is very far off the ground. Fitz doesn't think they can do it--it is too high off the ground. Dan tells him they will try. Fitz says, "I'll try anything as long as it helps the captain." Mark shows up at the door, throwing rocks at it. Murtrah allows him inside.


With lots of effort and fast talk, Mark and Steve get Murtrah to go into the store room but he insists Mark come with him. Mark gets him to mix liquids that he tells Murtrah will help him perfect the glasses' mixture. He also gets Murtrah to close the door and create a mixture of volatile gasses. While he does this, Fitzhugh and Dan climb up from the table to the door lock---across a ruler with a 60 foot drop below them. They manage to bolt the door; Dan almost falling. Mark slips out under the door and Murtrah tries to get out. The others cannot get the chain off. Steve demands they blow up the bomb but Mark leaves, going down to get some gun powder from the bomb to help blow the chain off. Steve asked, "What's he planning?" Dan looks, "I don't know but he usually makes sense." Steve sends Fitzhugh down to the bomb with orders to set it off if the giant gets out of the door--Murtrah is using an axe to try to cut out of the wooden door. Fitz protests--he will be the only one left, the girls, Barry, and "me." Steve yells at him and he goes. Steve hides behind the spray can to shield himself from the blast when the chain blows off. The three men climb down to the vent where Fitz was about to set off the bomb, apologizing. Steve tells him not to worry---and sends the three others out. Murtrah gets out of the store room. Steve triggers the bomb...but it won't work!


As Murtrah rushes out of the closet, Steve fixes the bomb, sets it off, and runs out the drain. Murtrah sees the spark and moves to pick it up...and is blown up. Fitzhugh tells Steve, "Good thing that stupid giant believed your tale of seeing Earth through those glasses." Steve counters, "He's not so stupid--I really did see the Earth through those glasses."