Amber White, a sweet social worker who lets destiny come to her, has her heart broken when the Bachelor, Brad, stands her up in the Bachelor finale, instead proposing to Bridgette (likely for her rockin' body). While out honeymooning in a cabin, Brad and Bridgette are both horrifically and mercilessly murdered by a mysterious figure. Before the figure finishes the deed, he demands to know why Amber wasn't good enough and then states that he will win The Bachelorette, stealing the ugly green engagement ring off of dead Bridgette’s finger.
Chris Harrison, a dream on camera but a nightmare off, is back to host the next season of The Bachelorette. ABC has threatened to cancel them due to dwindling ratings unless Chris can somehow pull off a smash hit season, despite a minuscule budget. For financial reasons, the season takes place on the private island of a nameless ABC exec, filmed with a skeleton crew of two dweebs (Bud and Kim), and starring Amber from the season prior. Amber brings her cat, Tomcat, to keep her company during the stay and remains positive about her situation, believing that “everything happens for a reason.” Amber meets the eccentric crew of 30 potential suitors, most notably Andrew, the level-headed software engineer who’s surprised how nervous he is to Amber, Ed, the IT Manager who’s headstrong for Amber, and Fergal, a kind but cowardly author. Tomcat performs a trick at the opening ceremony, dragging the first impression rose in his mouth up to Amber.
During the first cocktail party, Amber sees a cocky man named Henry defend Fergal from humiliation from a jerk named Lyle. Amber eliminates Lyle and grants Henry the first impression rose. Henry admits to a few other men that he doesn’t care about Fergal, but rather he’s “playing the game.” Later that night, while out for a smoke, Henry is drowned by a mysterious figure, presumably for his dishonesty to Amber. When Henry doesn’t show up for the first rose ceremony, the men competitively push to film it without him. Amber gives roses to 19 of the remaining men. The rest say their goodbyes and head to a ferry that takes them back to the mainland. Bud and Kim express concern about Henry still being missing, but Chris downplays it saying that something bad happening would only help their ratings.
The next morning, Henry is found dead in the pool, and another man is found dead having collapsed in the shower. Amber is devastated but believes them to be accidents. Chris tells everyone to continue with the season, but some men grow suspicious. During an athletic competition, a rugby ball explodes, killing another man which causes everyone to freak out. Andrew rushes Amber to her room for protection and attempts to console her amid the chaos, which Amber appreciates. The men, whose phones have already been confiscated prior to entering the island, demand answers from Chris. He tells them that there is no service on the island and that the ferry doesn’t return until the following week.
The men, confined to the mansion with nothing to entertain themselves with except alcohol and each other, throw a rager. With their guards down, three more men are murdered and discovered the following morning. A business card is found near one body, and Fergal, knowing that they were only handed out to a few people before Chris confiscated them, narrows the killer down to Andrew, Ed, a contestant named Brock, and Chris. Accusations are flung and Amber chastises the men for acting childish. Chris reveals to Bud and Kim that he has set up security cameras in their editing room and has guns for protection. His plan is to eventually escape on the ABC exec’s boat and zodiac stowed on the backside of the island. Bud and Kim see that Chris has a phone charging, unsure why he would have it out if there was really no service.
Ed checks in on Amber’s well-being. Amber agrees to a date with him, impressed with his compassion and thoughtfulness. Amber believes that she is ultimately safe because the killer only wants to eliminate the men. Ed tries to kiss her, but she rebuffs him. A few men explore the island and discover a shed with barrels of gasoline, leading them to believe there’s a boat on the island. Chris learns of their discovery. Not wanting anyone to get away, he hides the zodiac behind a tree and douses the inside of the boat with gasoline, but is interrupted before he can set it on fire.
With a newfound confidence, Amber decides that she will continue to go on one-on-one dates, determined to either find the killer or a husband. Fergal is selected as the first date, and they mutually agree that, although they respect each other, there is no romantic chemistry. While the men anxiously wait in the mansion, Andrew is attacked in the bathroom but he slays the figure. The figure turns out to be Brock. The men relax with the threat finally over. Amber is crushed to hear that Andrew was nearly killed, and uses that as a reason to have a date with him. They discuss their mutual love of the Beatles and they kiss, which Ed sees while hiding in the bushes.
One of the men discovers a business card on Brock’s person, meaning that he was not the original killer, sending the men into another panic. Chris forces Bud and Kim to edit the footage they have so far into a documentary special before they flee. Andrew and Ed look for Amber. Half of the remaining men stay put while the others go off in search of the boat. Amber runs from Ed and Andrew, unsure of who is lying, and Tomcat escapes during the confusion. Several men sneak into the editing room and find out that Chris’s phone had service the entire time, making him liable for all the deaths. Chris chases after them and shoots them, but is seen by three other contestants. They escape from Chris, only to be killed by a figure shortly thereafter.
Bud and Kim find Chris’s phone. They call 911 and use it as a hotspot to upload all of their raw footage to YouTube. The cohort of men that fled find the boat and depart, only for it to be engulfed in flames when a cigarette finds the pool of gasoline. Fergal finds a life jacket and abandons ship while the others burn. Bud, Kim, and Chris meet at the Zodiac. The assistants tell Chris about alerting the cops and uploading everything. Chris realizes that there is now public footage of him murdering people and shoots himself, deciding that suicide is a better fate than being “canceled.” A terrified Bud and Kim take off in the Zodiac and rescue Fergal at sea.
Only Amber, Ed, and Andrew remain on the island. Having fallen for both, but believing one to be the killer, Amber doesn’t know what to do. While Andrew is stating his case for innocence, Ed attacks him. Amber shouts at them to stop, but they fight on the lawn. They trip each other, trying to get to a gun that has been discarded on the grass, but before they can reach it Tomcat drags it to Amber. Amber threatens to shoot them until they stop fighting. Ed screams at her to kill Andrew, for he is obviously the killer. Instead of defending himself, Andrew asks that Amber only let him live if she truly loves him back. Rather than listening to Ed’s demands, Amber finally makes a decision and shoots Ed in the heart, cementing his legacy as the killer, regardless of the truth. At the request of Amber, they burn down the mansion using the leftover gasoline to give their relationship a fresh start and put the harrowing experience behind them. Together, they sing “I’ll Follow the Sun” by The Beatles as they wait for help to arrive.
One year later, Amber and Andrew watch a video of an interview with Fergal, who has since achieved success publishing a book about his experience on the island. While Amber leaves the room, Andrew presents Tomcat with a new collar adorned with the green gem from Bridgette’s engagement ring, revealing Andrew to have been the killer all along. Andrew goes outside to accompany Amber. She kisses him, happy with her choice.