Sandman comes to an end with the Fleisher, Kirby and Wood story in issue 6 (Dec/Jan 75/76).
The cover scene is part of the opening sequence. Sandman determines that the nightmare Jed is having is not natural, that it is being broadcast into his mind. Going to investigate, he winds up captured by Dr. Spider's men. Dr. Spider sends a dream version of Sandman back to the Dream Dome to get Brute and Glob out of the way. Glob falls for the impostor, but Brute is suspicious.
As for Jed, he continues to be used as slave labour by his aunt and uncle. They are taking his cousins to a carnival, but Jed has to stay behind and work. Cousin Bruce offers to let Jed go in his place if Jed will give him his sonic whistle, but Jed refuses.
That evening Bruce sneaks into Jed's room and grabs the whistle. He blows it, which summons Brute. Brute gives Bruce a bag of nightmare demons, and then wakes Jed. He explains that Sandman has gone missing, and he needs Jed's help to save him.
Meanwhile, in a great scene, Dr. Spider's ransom demand to the government for Sandman is openly mocked by the media. While Dr. Spider fumes about this, Sandman finds a crack in his crystal cell and bursts out.
Jed and Brute show up, and though Jed is decoyed by the fake Sandman, Brute destroys the creature.
All three fight against Dr. Spider and his goons. Dr. Spider flees in a rocket, and Jed is returned to his unloving family.
There was another issue of Sandman written and drawn which was not published at this time. A few years down the road it almost saw print in an issue of Kamandi, but then that book was cancelled. So the story was twice unpublished, instead of the usual once.
It did finally get released in 1982, in a Best of DC digest.