Is there a list of essential jrpg's for the PS4?

Yeah, well to be fair "Heartless/Darkness are devouring worlds including your own and only you have the power to prevent it, oh yeah by the way, the other worlds are from movies you grew up with" is good enough for me.

Compartively, Wiki has a pretty decent full plot summary: >!Following Master Xehanort's return, Yen Sid begins preparing for seven Keyblade wielders to counteract Xehanort's plan to forge the χ-blade using a reconstituted Organization XIII. Sora, who was nearly taken over by Xehanort,[b] discovers that he has lost much of his own strength as a result. Accompanied by Donald Duck and Goofy, Sora resumes his travels across other worlds in order to regain his "power of waking", the ability to restore lost hearts. Meanwhile, Riku and King Mickey traverse the realm of darkness in search of Aqua, while Kairi and Lea train to properly wield their newly obtained Keyblades.

During their travels, Sora and Riku are contacted by Ienzo, who discovers via Ansem the Wise's research data that Sora's body contains the hearts of Roxas, Ventus, and Xion. Riku surmises that the Organization's members from the past are using artificial human replicas created by Vexen as vessels that enable their existence in the present, which inspires Sora to restore Roxas by transferring his heart into a replica body. Meanwhile, the Heartless Ansem enters the realm of darkness and kidnaps Ansem the Wise, corrupting Aqua's heart in the process. However, Vexen reveals himself to be a double agent loyal to Ansem the Wise, whom he helps rescue before sending a spare replica to Ienzo for Roxas to inhabit.

Riku and Mickey eventually locate and battle the corrupted Aqua in the realm of darkness. At the same time, Sora discovers Master Eraqus's Keyblade on the Destiny Islands and uses it to enter the dark realm, where he exorcises the darkness from Aqua and returns her to the realm of light. Sora, Donald, and Goofy then follow Aqua to Castle Oblivion, which she transforms back into the Land of Departure to awaken Ventus. When she is attacked by Vanitas, Sora rediscovers his power of waking and revives Ventus, who fends Vanitas off.

The seven Keyblade wielders depart for the Keyblade Graveyard to battle the Organization, only to be quickly consumed by a swarm of Heartless summoned by the possessed Terra. Awakening in a limbo realm called The Final World, Sora is guided back to the realm of light by Kairi and uses the power of waking to revive his friends. Returning moments before their initial defeat, the guardians of light successfully destroy most of the Organization's members; in the process, Terra regains control of his body and reunites with Aqua and Ventus, while Lea reunites with Xion, whom Vexen recreated for the Organization, and Roxas, who regains his own heart to protect Lea and Xion.

Once Xehanort remains the last Organization member, he provokes Sora into attacking him by destroying Kairi's body, allowing Xehanort to acquire the χ-blade and summon Kingdom Hearts. Using Xehanort's power of time travel against him, Sora, Donald, and Goofy transport him to his boyhood training grounds of Scala ad Caelum, where they defeat him. After the other Keyblade wielders rejoin them, Eraqus's heart emerges from Terra and convinces Xehanort to surrender. As Xehanort succumbs to old age, his and Eraqus's hearts depart together to The Final World, while Sora and his friends use the χ-blade to close it and return to the Keyblade Graveyard.

Sora decides to use the power of waking to revive Kairi; despite warnings that his repeated misuse of this power could result in him losing his heart, Sora promises to return. Afterwards, Sora's friends gather at the Destiny Islands for a celebration, where Kairi stays beside Sora before he fades away. In a post-credits scene, Xigbar, who survived the Keyblade War, retrieves Xehanort's Keyblade and summons four of the five Foretellers, revealing himself to be a reincarnation of their fellow Keyblade apprentice, Luxu. He begins to recount his actions to the Foretellers, with Maleficent and Pete watching from afar. In a flashback to their youth, Eraqus and Xehanort begin a new game of chess that predicts a battle between Sora, Luxu, the five Foretellers, and the Master of Masters.!<

No where in that does it really tell you why you're going from island to island. You just do it and it essentially runs parallel to the above and every now and then there's a princess reference. The story itself doesn't do enough for me, even knowing the details of the other games, because it's just not that good.

/r/JRPG Thread Parent