After nearly three months in the Big Brother house, Kaycee, a 30-year-old pro football player from San Diego, CA, who currently resides in Tempe, AZ, took home the grand prize of $500,000 via a tight 5-4 jury vote over fellow houseguest, Tyler, a 23-year-old lifeguard from Rossford, OH, who currently resides in Hilton Head, SC.
JC, a 28-year-old professional dancer from Miami, FL via Spain, who currently resides in West Hollywood, CA, finished the game in third place.
The Season 20 finale of Big Brother picked up where Sunday night's episode had left off, with the Final 3 houseguests competing in Part 1 of the final Head of Household competition. The players were required to hold onto their jetpacks for as long as possible while they soared above a city skyline and were sprayed with blue fuel.
The last person left standing would win Part 1 and automatically earn a spot in the third -- and final -- part of the competition, which would feature the champions of Part 1 and Part 2 facing off for the title of Head of Household.
Tyler and Kaycee had planned for Tyler to throw Part 1 since it was an endurance challenge -- which is Kaycee's strongsuit -- and then for Tyler to win Part 2 -- which is typically a mental competition -- so they could meet up in the third round, ensure victory for one of them, and then go to the Final 2 together.
However, Tyler wasn't sure it was good for his game to be throwing any type of competition this far into the season.
After 54 minutes, JC dropped from the challenge first, and he was pretty disappointed in himself. After 56 minutes, Kaycee dropped.
Tyler was glad his fate in the game was going to be in his own hands. Tyler hoped his decision wouldn't result in a loss of Kaycee's trust and loyalty. While she was annoyed, Kaycee said she still intended to "destroy" JC in Part 2 of the competition.
For Part 2 of the final HoH Competition, Kaycee and JC were instructed to program a laser to carve faces of previously-evicted houseguests into a fake mountain. They were given clues about houseguests in order to determine whose faces should be drawn.
Kaycee won the second part of the HoH competition by only about one minute, and she cried tears of joy.
Even though Tyler was confident in his alliance and Final 2 deal with Kaycee, he told the cameras he needed to win in order to ensure he'd have a shot at the $500,000.
Part 3 of the final HoH competition then commenced and it was called "Jury Outcasts." Tyler and Kaycee were shown videos of previously-evicted houseguests saying facts about themselves, and the pair had to figure out whether such statements were "Totally Right" or "Not Quite."
For each correct answer, a player would receive one point. The houseguest with the most points at the end of eight rounds would become the final Head of Household of the summer.
It was an extremely close and exciting match, as Tyler and Kaycee guessed the same answer in every single round. They even got the same one question wrong.
In a tiebreaker question, Big Brother host Julie Chen asked, "In seconds, how long was the jetpack attack competition from the official start to when Kaycee made contact with the ground, making Tyler the winner?"
Kaycee was the closest in guessing 3,400 seconds, because the correct answer was 3,413 seconds. (Tyler's guess was 2,002 seconds).
Kaycee therefore won the final Head of Household competition, and she got to choose whether to take Tyler or JC to the end with her. Tyler reminded Kaycee they had made a Final 2 deal with each other extremely early on in the game and he hoped she'd keep her word.
And Kaycee did just that. She voted to evict JC.
"I came here to play this game and I know I have to lie a lot... so I thought, 'Let me play this really dirty game,' but I was loyal all the time and I think that's what screwed me... like defending, Tyler, he was my No. 1," JC told Julie in his post-eviction interview.
It then became time for the jury's live interrogation of Tyler and Kaycee that would help determine this season's champion. JC and the other jurors were allowed to ask Tyler and Kaycee questions about their strategy, motives, mistakes, moves and more.
Kaycee was asked about her best strategic moves -- not physical -- and she said it was her social game and establishing relationships with people on the other side of the house who were not in "Level 6."
Meanwhile, Tyler told the group his best strategic moves had to do with his multiple Final 2 deals with players and a secret "Power App" no one knew about that he never even had to use.
Tyler and Kaycee also expressed how they're both Super Fans of the game and cared about each and every single person in the house.
In her final speech, Kaycee insisted she played a very loyal game and didn't make a promise she could not keep, while Tyler reiterated his big moves, secret alliances, and being an occasional puppetmaster. Tyler said he allowed people to think he was a wide-eyed and confused lifeguard, but in reality, he knew what was happening every single week of the whole summer.
The jurors then cast their votes for the winner of Big Brother's 20th season.
In a shocking turn of events, Chris "Swaggy C" Williams proposed marriage to Bayleigh during the live finale, and she whole-heartedly accepted.
In addition, Julie announced Celebrity Big Brother will be returning to CBS this winter.