It's Genius All-Stars season and producers picked top 3 from each of the previous seasons:
- Hong Jinho, Kim Kyungran and Lee Sangmin from Rules of the Game
- Lee Sangmin, Lim Yohwan and Yoo Junghyun from Rule Breakers
- Jang Dongmin, Oh Hyunmin and Choi Yeonseung from Black Garnet
plus a few random characters, such as human disaster Kim Kyunghoon, season 1 "i'm a woman" Choi Jungmoon, game's first ever boot Lee Junseok, lawyer Lim Yoonsun and poker player Kim Yuhyun.
Players enter one by one, get acquainted with each other and have traditional Genius banter with copious jokes about Jinho's bad pronunciation.
This season's gimmicks are garnet matches and how deathmatches are picked by players themselves. There are 3 garnets matches spread around season 4 and in them player with the most amount of garnets at the end wins and the one with least garnets — automatically goes to Deathmatch. This should prevent a player like Yohwan who regularly had 0 from floating by avoiding Deathmatches and will force everyone to actively play in main matches and pursue garnets.
All Deathmatches this season are repeats from previous seasons. Deathmatch opponents can veto three games each and then deathmatch game is decided by random draw among the rest.
First Main match is ID Exchange. All 13 players are given random cards: 7 "commoners", 5 "nobles" and 1 "convict". Denomination of the card is written with invisible ink and can only be seen using special light on dealer's table. Players can peek which card they got at first and then start trading with each other.
Official trading procedure is done through dealer's table. After trading players can look what cards they got using black light lamps. Players can trade cards "unofficially" among each other but then they cannot confirm what card they got.
If noble and commoner cards are traded on dealer's table (former) noble gets 1 point. If convict card is exchanged with commoner card, the original convict gets 2 points. The last player who trades away convict card gets extra 3 points. At the end of a main match each 3 points are converted into garnets.
Sangmin being his usual self starts a big alliance starting from brains Hyunmin and Jungmoon, with Kyungran assigned as security officer of sorts to keep an eye on others and he also brings in Junghyun because... for some reason.
Yoonsun, Kyunghoon, Junseok and Yohwan make 2nd team. Kyunghoon swears not to betray his new teammates. But of course the second Dongmin comes and asks if he wants to work for him he agrees immediately.
Dongmin, Jinho, Yeonseung and Yuhyun form a third alliance.
Yoonsun wants to get some points as fast as possible so she asks Kyunghoon who has commoner card to trade with her. Dongmin however ordered him not to trade (because commoner cards being the only source of points are valuable). Kyunghoon tries to wiggle yourself out of it but still says he will trade with his team after one trade. Yoonsun trades with Yohwan and now Kyunghoon is up. To keep his promise to Dongmin in some stupid twisted way he swaps his card with Sangmin in a corridor and then trades that card with Yohwan.
He doesn't know that Sangmin had the convict card so when Kyunghoon asks him to trade with him "unofficially" (as in: without dealer's involvement and hence no check what the card you got really is) Sangmin readily agrees to offload his card to that dumbass. Kyunghoon then unknowingly trades convict with Yohwan.
After the trade quiet Yohwan doesn't freak out and just calmly asks why Kyunghoon didn't tell him that he had THAT from the beginning. Only then Kyunghoon starts to realize his mistake. Kyunghoon feels bad for Yohwan so he trades with him once again this time unofficially, getting back convict card and then comes to Sangmin and begs him to take his card back. Sangmin is amazed at such stupidity.
Dongmin's and Sangmin's teams merge. Hyunmin in the now big group is still calculating how to achieve equal points for everyone and get joint win. He comes up with a plan to bring in 2 more people from minority group and freeze out 2 remaining people.
Kyunghoon has confessed that he holds convict card after which lawyer Yoonsun and Junseok ditch their team and joined majority, leaving only Yohwan and Kyunghoon outside of it destined for Deathmatch against each other. Junseok however has a plan of his own, he talks with Yohwan and eventually wants to make a series of trades between him, Yohwan and Kyunghoon at the very end to rack up more points and become sole winner.
To guarantee safety in a big 11 people alliance Hyunmin suggests using the same noble and commoner cards each time for trades and publicly share them between each other thus completely eliminating the risk.
Sangmin senses the Junseok's betrayal so he arranges that Junseok gets his shared 4 points before everyone else so then he would not have a plausible reason to partake in late game trades. However after getting 4 points and holding a "safe" commoner card he tries to run with it and suddenly wants to "talk" to Kyunghoon. Everyone freaks out and this creates a big commotion. With all this drama, people don't notice Sangmin leaving Kyunhoon's room just as big crowd gathers around Junseok to prevent him from ruining joint 11-way win.
Eventually big crowd gives up on convincing Junseok and they decide to make do with their remaining cards. They still have a "clean" noble card that they're are sure about and just need to find the commoner. Sangmin trades with Yoonsun, gets commoner card and it becomes a new "clean" card. Sangmin gives up commoner and gets "clean noble".
There are only 2 minutes left and Sangmin trades his clean noble with Jungmoon through dealers. She then gives her "clean noble card" to Junghyun who now has to officially trade with Sangmin to complete joint win.
And then Sangmin suddenly doesn't want to trade anymore. Junghyun thinks it's because Sangmin has convict card and feels sorry for him. Sangmin hugs him and whispers that it's Junghyun who has the convict already.
Flashback.
Sangmin takes pity on Kyunghoon, takes his convict card and tells him to act like he still has it. Then, when he is given clean noble card by his team he switches it with convict card and gives it to Jungmoon. Jungmoon who apparently worked on her poker face and managed not to reveal his betrayal, proceeds to give this card to Junghyun. Junghyun is the final convict and obviously Sangmin doesn't want to trade with him.
Game ends and Junghyun loses. Sangmin who betrayed 11 people because he felt bad for Kyunghoon gets sole victory, one extra garnet and one additional token of life that he gives to Hyunmin.
Junghyun picks Junseok as his opponent because his rogue actions ruined majority's joint win. They are playing Black and White from season 2. Junghyun who last time lost to Yohwan because he put lesser tiles first is now playing more aggressively. Junseok however reads him and manages to get rid of his zero and smaller tiles earlier and saves his higher tiles to the end which wins him the game, eliminating Junghyun.
This episode contains the following tropes:
- Bad Liar: averted with Jungmoon. In season 1 her poker face was awful and her role as a zombie was instantly discovered. This time around when Sangmin sticks her with convict card, she doesn't even flinch, tells that it is a noble card and then just passes it along to Junghyun.
- Chain of Deals: trades, both through dealers and unofficial ones are the main component of ID Exchange. Final path of convict card is: Sangmin (unofficial) → Kyunghoon → Yohwan (unofficial) → Kyunghoon → (unofficial) Sangmin → Jungmoon (unofficial) → Junghyun.
- Commonality Connection: Jinho immediately proposes that he, Sangmin and Dongmin, as the "Three Kings" (winners of the previous seasons) should logically form an alliance. When Hyunmin joins the group, Sangmin instead suggests a "3 Min Alliance" between himself, Dongmin and Hyunminnote .
- Crush Blush: Dongmin's CGI blush when Jungmoon enters.
- Dresses the Same: once again, Jinho and Junseok are wearing similar outfits.
- Deadly Hug: At the end of the main match Sangmin doesn't want to trade his card with Junghyun. Junghyun who always thinks good of others, says it's because Sangmin has a convict card and doesn't want send him to the Deathmatch. Sangmin smiles, hugs him and whispers that Junghyun already has a convict card and he lost the game.
- Leitmotif: each entering player has a tune reflecting his or her character:
- Magnificent Bastard: Crazy bastard Sangmin betrays 11 people
. - Speech Impediment: as per usual Jinho causes quite a lot of jokes about his mumbling pronunciation and stuttering.
- Chaotic Stupid: "Titty God" Kyunghoon fully lives up to his reputation of being "a game destroyer".
