The Atom's quest comes to an end in Super-Team Family 14 (Dec/Jan 77/78), teaming him with Wonder Woman against the Secret Society of Super-Villains, in a story by Conway, Jones and Tanghal.
The story follows events from not only the last issue of SSoSv, but also from a one-shot Special, in which Wonder Woman played a role. The Secret Society had stolen Jean Loring from the Atom, and Grodd intends to use her as a weapon.
Star Sapphire had been mind blasted by Grodd, but gets her senses back towards the start of this story. She and Funky Flashman have no intention of going through with Grodd's schemes, but he has recruited the Floronic Man, who basically kidnaps Star Sapphire and drags her off to Gorilla City. Floronic Man had last been seen a year earlier in the Green Lantern back-up series in the Flash, when Jason Woodrue first became the altered plant master.
Together, Grodd, Star Sapphire and Floronic Man defeat Solovar and his forces and take over Gorilla City. We learn that Floronic Man is planning to turn on Grodd as well, wanting to wipe out all humans on Earth, while Grodd just wants to enslave them.
As for the Atom, he hooks up with Wonder Woman to stop an attack by alien robots in New York City, and then she brings him to Paradise Island, where they consult the Crystal of Knowledge. Never seen before or since, I like to think this was really just the Magic Sphere. They learn that Jean Loring is now in Grodd's hands, but when they head out to Gorilla City Star Sapphire uses her gem beam powers to take out the Invisible Plane. It crashes, and both heroes get imprisoned by the Society.
Grodd hooks Jean Loring up to a machine that has much the same effect as that of the Wind Pirate, causing all manner of natural disasters to take place around the world.
Star Sapphire had fried the Atom's size and weight controls with her gemstone, so Ray Palmer actually pulls the Atom costume off of himself, and somehow survives this, although the parts of him not in the costume should have enlarged instantly and cut him into pieces. Freed, he releases Wonder Woman, Solovar and the other imprisoned apes in Gorilla City, and they attack Grodd.
This time they fare far better. The Atom steals Star Sapphire's gem, and uses it to aid Wonder Woman against Floronic Man.
Then he overloads the machine that Jean is hooked to. The resulting explosion takes out Grodd, though Star Sapphire and Floronic Man get away, returning in the next issue of Secret Society of Super-Villains. Grodd gets imprisoned by Solovar, but gets free pretty fast and is back with the others in the next issue of SSoSV as well.
The explosion also seems to have shocked Jean Loring back to sanity, and removed the last of her destructive powers. She and Ray decide it's time for them to get married, and this leads into events in the following issues of Justice League of America, their stag and hen parties, and the wedding, as Ray debates telling her he is the Atom.
The final page is a tease for the following issue, teaming up the Flash with Orion, Lightray and Metron of the New Gods.