KQVI is definitely one of the most intriguing and complicated King's Quest games there is.
It begins with Prince Alexander moaning and groaning about his lost love Cassima. He can not figure out where the Land of the Green Isles is, where she said she lives. Though they met only for a few minutes in Mordack's castle, he knows he loves her.
Merlin's Mirror shows him the love of his life and, though it does not look like she is in immediate danger, he feels she is in trouble and is unable to defend herself. Alexander decides then and there that he must make it to the Green Isles. How does he make it there if he can't find it? He follows the stars outside of the tower room the mirror showed him.
(Although, another story is that Derek Karlavaegen had visited the Green Isles when he was a child, and though he produced a guidebook for it, the King and Queen of the Green Isles did not want it sold and he respected their wishes... but Alexander seeked him out for help in finding Cassima.)
Next thing we see is Alexander lying on the beach of what we later find out is the Isle of the Crown. There was a shipwreck on the treacherous reefs that surround the country.
Alexander wakes up, does a bit of exploring on the beach (his signet ring and a small copper coin) and makes his way inland. At the first (and only) fork in the road, Alexander (here on referred to as Alex, to save my typing fingers) makes the split decision to go towards the castle.
He tries to enter, but the Guard Dogs will not allow him. He shows his signet ring to the guards and the retrieve Captain Saladin. The captain takes Alex to see Abdul Alhazred, the vizier of the castle. He explains that Cassima's parents, King Caliphim and Queen Allaria, died when she was held captive... and now she is mourning their loss in complete seclusion.
Alex points out that it has been nearly a year... to which Alhazred responds that after Cassima's mourning period is over, he and she will be married. Alhazred then insists Alex should start making immediate preperations to return home.
Alex, knowing that it will be difficult to return home since he has no ship and the currents are treacherous, stays on the island. He heads into town where he meets Jollo in the bookshop (the court clown who tells Alex quite a bit about Cassima), the bookstore owner Ali, and the owner of the pawn shop Hakim.
While in the bookshop, he opens a book and a poem falls out. Ali, being the nice man he is, tells Alex to keep the poem. Alex also sees a book of spells on the counter in the bookshop and finds out that he can have it if he brings in a rare book.
Alex continues through town, sees a girl picking roses named Beauty, and heads to the docks. He meets the ferryman, Hassan, who tells him many stories about what has happened to the Land of the Green Isles since Alhazred came to the land. He also tells Alex of a magic map that is supposed to exist.
Alex meets up with the Hakim and trades his signet ring for the magic map. He then uses the copper coin (which has his mother's face etched on it) to trade for a wind-up nightingale. As he leaves the shop, Hakim is dumping some trash. Alex goes through and finds a bottle of invisible ink.
He goes to the beach and uses the magic map to travel to the Isle of the Sacred Mountain, where he sees an enormous cliff, but picks up a flower and black feather.
He then goes to the Isle of Wonder. There he meets an oyster who can't sleep. Alex reads to him, and when the oyster yawns, Alex grabs the pearl inside the shell... and the oyster goes right to sleep. Just before Alex makes it inland, he meets with the Guardians of The Isle of Wonder.
Each has a different sense. The one that smells, Alex shoves the flower under his nose; the second has ears, so Alex winds up the nightingale; the third has a large tongue, and Alex gives it a mint; the fourth has sensitive hands, so Alex puts out a rabbit's foot. The fifth has eyes, so Alex pours the invisible ink over himself. And that's the last Alex sees of them.
Traveling to the Isle of the Beast, Alex throws the lettuce into a boiling pool and the pool stops boiling. He picks up a lamp and on his way back to the beach, meets a Dangling Participle.
He takes it and returns it to the bookworm and receives a rare book in return. Alex then heads back to the Isle of the Crown to get the spellbook from Ali.
At the crossroads, though, he meets a nightingale singing in a tree. Jollo had informed Alex of Cassima's nightingale Sing-Sing, so he winds up the mechanical one, which causes Sing-Sing to befriend Alex.
He then heads to the pawnshop and trades the pearl for his signet ring and the nightingale for the flute. He then goes to the bookstore and gets the spellbook. When Alex ends up back at the crossroads, he gives Sing-Sing the signet ring. Cassima receives it and sends a length of red ribbon to him. How does Alex know it's Cassima? He sees a strand of long black hair in the ribbon and knows that it's from her.
Alex begins going to the different islands, trying to collect the ingredients of the spells. Pretty long story, so I'll try to jump ahead. He also sends the love poem to Cassima to let her know that he still loves her.
Cassima sends a letter in reply:
"My Dear Alexander, You have truly come at the darkest hour both for the Isle of the Crown and for your Cassima. I gain new courage knowing you are near - but I beg you, do nothing to endanger yourself. Beware Alhazred and the djinni who serves him. Cassima."
Alex does more trading with Hakim and then heads to the Sacred Cliffs. He looks at the cliffs and sees a riddle. He presses the letters of the riddle to solve it and steps appear in the mountain side. He had to solve four other puzzles before he reached the top of the cliff.
As he travels, he finds the City of the Winged Ones and is brought in front of Lord Azure and Lady Aeriel, where he is informed that he must save their daughter Celeste from the Minotaur who inhabits the catacombs.
Alex takes up the challenge and enters the catacombs. He solves several puzzles in there to make his way through the maze. And yes, he does save Celeste by entering the lair, waving a red scarf in front of the fire, and the minotaur running at it and into the fire. Nice summary? Hope so :P
Even from rescuing their daughter, the Lord and Lady were not very gracious... and that if he comes back, he will be killed. However, before he leaves, Alex is granted a meeting with the Winged Ones' Oracle, who tells him she will not persuade him to leave, but hands him a vial of her sacred water.
As Alex goes to leave, he sees a fifth island appear on the map - the Isle of the Mists. Alex goes there, grabs a few things, and heads back to the Isle of the Beast.
This time, he makes it to the castle and is met by the Beast. He is told that he must find someone to break the curse on him.
Alex rushes to the Isle of the Crown, makes a quick stop in the bookstore where Jollo tells him that the wedding is tomorrow. He also says that he may be able to switch the genie's lamp with a duplicate. Alex goes to the girl Beauty and gives her a white rose from Beast's garden. She quickly makes the decision to go with Alex to become the Beast's bride. As Beauty and the Beast hold hands (well, his paw in her hand), they both transformed: Beast into the handsome Prince Cocteau the Thrice Blessed, and Beauty into a beautiful gown.
Alex continues to travel the islands collecting spell ingredients. Then he goes to the Isle of the Mists.
He is captured by the Druids who live there and just before they burn him, he casts a spell to make it rain. He makes friends with them and they tell Alex that he must travel to the Land of the Dead to rescue Cassima's parents in order to stop the wedding.
By using Night Mare, the horse that flies between worlds, he will be able to do so...and then he must challenge the Lord of the Dead (Lord Samhain) and defeat him. So, Alex travels back to the Isle of the Sacred Mountain, tames Night Mare and heads to the Land of the Dead.
There, Alex soon meets King Caliphim and Queen Allaria. They tell him that Alhazred murdered them in their beds and that Alex must do what he can to have them returned to the land of the living.
Summary: Alex meets a few ghosts, helps them out, grabs more spell ingredients, and then meets the Lord of the Dead. He challenges him and is told that he must make the lord cry. Alex pulls out the mirror from the Beast, the mirror of Truth, and shows it to the lord. Images of pain and suffering, murder and torture, and betrayal appear. This remides Samhain of his past and present... and he cries.
Alex takes the King and Queen back to the Isle of the Crown on Night Mare. However, the King and Queen decide that they must go to the different islands to try to restore peace while Alex does his best to protect Cassima.
Alex walks into town, meets with an old lamp-seller, and trades the lamp he had gotten from the Isle of the Beast for a bottle that should look like the lamp that Jollo described.
He then walks into the pawnshop where a cloaked man (the genie) is waiting. Alex puts on a show with a drink he has that will stop his heart. He makes it look as if he has died, so that when the genie returns to Alhazred he will report Alex's death.
It is time for Alex to head to the castle. He walks around to the side and paints a door onto the wall, casts a spell, and enters.
He helps a lost child ghost find his mother, for which the boy repays Alex by telling him about a secret passage in the castle where Alex can talk to Cassima.
Alex meets up with Jollo, hands him the fake lamp and then heads to the secret passage. He heads up and sees a second passage that leads him to Alhazred's empty bedroom.
He finds a note from Shadrack to Alhazred, both members of the Black Cloak Society. It is incriminating evidence that proves that Alhazred has killed the king and queen and is planning on killing Cassima once they are married.
He returns to the secret passage and sees a hole in a wall and hears weeping on the other side. Knowing that it's Cassima, he gains her attention and shows her the letter. Then he gives her a dagger in hopes that she will be able to protect herself. She tells Alex to show the letter to Saladin in order to save her and hopefully incrimidate Alhazred.
Once Alex leaves the secret passage, he heads to a door that must be opened with a magic word. He goes in and sees the treasures of the different island rulers, all that the rulers thought were stolen by those of other islands.
He then heads upstairs to the Grand Hall in hopes of stopping the wedding. He meets with Captain Saladin and shows him the letter. Saladin believes the letter is a fake and takes Alex into the throne room to show that Cassima is happy about the wedding.
Just as Alhazred is beginning to rage that Alex is there and that Saladin did not follow commands, King Caliphim and Queen Allaria walk into the throne room, followed by the Druids and soldiers of other islands. Allaria can tell right way that the woman standing next to Alhazred is not Cassima. Suddenly Cassima shimmers and the genie appears in her place.
Alhazred runs up some stairs to a tower room and Alex follows. In the tower room, Cassima lays bound and helpless on the floor. Jollo gives Alex the genie's (real) bottle, so that Alex becomes the master of Shamir.
Alhazred and Alex begin to swordfight as Cassima struggles with the ropes. Good thing Alex gave her the dagger, or she wouldn't have been able to cut the bounds. She stabs Alhared in the shoulder and Alex knocks him unconscious.
Alex and Cassima kiss and soon after, a wedding follows...but this time, the wedding of Alexander and Cassima.
Because of the genie, Graham, Valanice, and Rosella are able to make it to the wedding. Caliphim and Allaria declare they are too old to rule and that Alex and Cassima will be the new rulers of the Land of the Green Isles. Long Live King Alexander and Queen Cassima!