Here are 100 storylines (in no particular order) from now through the beginning of the Games on Aug. 5 and the Closing Ceremony on Aug. 21:
2. Michael Phelps. One last Olympics for the most decorated Olympian of all time. He’s swimming faster than he has in six years, after a 20-month competitive retirement, a six-month suspension for a DUI and some dark times.
3. Usain Bolt. One last Olympics for the fastest man of all time. The sprint king, who turns 30 on the day of the Closing Ceremony, is more vulnerable to defeat than the previous two Games.
4. Phelps and Bolt. They’ve never met.
5. Will LeBron James commit to a fourth Olympics?
6. Stephen Curry‘s Olympic debut after a long season (and now an injury)?
7. Brazil’s many issues — from politics to economics to the Zika virus to water quality to Games readiness — ahead of the first Olympics in South America.
8. The Independent Olympic Athletes marching into the Opening Ceremony, immediately before host Brazil. This group led out by the Olympic flag is expected to include refugee athletes.
9. The U.S. has a medal threat in modern pentathlon. Margaux Isaksen missed bronze by eight points in London and can become the first American to earn a medal in the event since 2000.
10. Russia’s track and field team, currently banned.
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11. Maria Sharapova, currently banned.
12. Martina Hingis playing the Olympics for the first time in 20 years, with Roger Federer.
13. Women will carry the U.S. Olympic team, as they did in London:
14. Serena Williams and Venus Williams, how much longer will we see them compete on the same court?
15. Gwen Jorgensen nearly quit triathlon, then went undefeated for nearly two years up until three weeks ago. The former Ernst & Young accountant can become the first U.S. Olympic triathlon champion.
16. Wrestler Adeline Gray has won 37 straight matches since July 2014. She can become the first U.S. Olympic women’s wrestling champion.
17. Gymnast Simone Biles hasn’t lost an all-around competition in nearly three years. She’s already arguably the greatest female gymnast ever, and a first Olympic gold could cement it.
18. Boxer Claressa Shields is 69-1 in her career. An opponent’s trainer threw in the towel at the 11-second mark of a 2014 World Championships bout.
19. Swimmer Katie Ledecky hasn’t lost a 200m, 400m or 800m freestyle since Jan. 18, 2014, and could become the second Olympian to sweep those events at a single Games. Not to mention potential relay medals.
20. The U.S. women’s water polo team can continue an unprecedented run of dominance. It holds every major title — Olympics, World Championships, World Cup and World League.
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21. One last go-around for the UConn crew of Sue Bird, Diana Taurasi and Geno Auriemma? The U.S. women’s basketball team has won 41 straight Olympic games since 1992.
22. The future of Team USA — Brittney Griner, Elena Delle Donne and Breanna Stewart.
23. A U.S. women’s soccer team lacking several World Cup players is not ruling out a boycott. But is still a massive favorite with Carli Lloyd, Alex Morgan and Hope Solo.
24. The U.S. women’s volleyball team is also the reigning World champion, with Olympic volleyball legend Karch Kiraly at the helm. “We know, two years from now, the headwinds will be great in Rio,” Kiraly said immediately after the Americans broke a 62-year World Championship drought in 2014. Kiraly was referencing Brazil, then the world’s top-ranked team, that the U.S. stunned in the Worlds semifinals.
25. Potential U.S.-Brazil showdowns in men’s and women’s beach volleyball and judo. Kayla Harrison, who became the first U.S. Olympic judo champion in London, is rivaled by Brazilian Mayra Aguiar.
26. Kerri Walsh Jennings and her new partner, April Ross. Walsh Jennings forged their partnership at the net immediately after the London 2012 final, where she and the (now-retired) Misty May-Treanor beat Ross and then-partner Jennifer Kessy.
27. Phil Dalhausser and his new partner, Nick Lucena. They were partners until 2005, then split with Dalhausser winning 2008 Olympic gold with Todd Rogers. Now they’re back together and arguably the biggest threat to Brazilian World champions Alison and Bruno.
28. Golf’s return to the Olympics. Four major champions have already bowed out.
29. Rugby’s return to the Olympics. Both U.S. teams have qualified.
30. New England Patriots safety Nate Ebner looking to add an Olympic rugby berth to his Super Bowl title.
31. Jillion Potter fighting cancer and coming back to captain the U.S. women’s rugby team.
32. In basketball, Canada and France each have a bevy of NBA players. But only one nation can qualify at a last-chance tournament.
33. The U.S. men’s boxing team must pick itself up after failing to win a medal for the first time in London.
34. Brazilian canoeist Isaquias Queiroz, nicknamed “Sem Rim” (no kidney) after a childhood fall that caused the aforementioned organ problem.
35. Chinese badminton. Superstar Lin Dan seeks his third straight Olympic title, but countryman Chen Long is the two-time reigning World champion.
36. In women’s doubles, Yu Yang is a gold-medal threat. You may remember her from the London badminton match-throwing scandal.
37. Brazilian beach volleyball fans on Copacabana Beach.
38. A Summer Olympics (close to) the U.S. time zones for the first time since 1996.
39. Michael Phelps and Chad le Clos renew their butterfly rivalry. And their chirping.
40. Phelps and Ryan Lochte going head-to-head for the final times at the U.S. Olympic Trials (June 26-July 3) and, potentially, in Rio. Look for them together in the 200m individual medley and possibly the 100m butterfly and 200m freestyle.
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41. Missy Franklin and Katie Ledecky going head-to-head in the 100m freestyle and 200m freestyle.
42. Franklin in particular. She has not looked like the swimmer who won four Olympic golds in 2012 and six World golds in 2013.
43. The men’s 4x100m freestyle relay. The most exciting event at the Olympics. Know the name Caeleb Dressel.
44. A Japanese swimmer by the name of Kosuke Hagino. He was the world’s best all-around swimmer — above Phelps and Lochte — until a bike fall kept him out of the 2015 Worlds.
45. China’s Ye Shiwen. She was the eye-popping revelation of the 2012 Olympics, sweeping the 200m and 400m individual medleys at age 16. Her 400m IM world record included swimming the final 50 meters of freestyle faster than Lochte did to win the men’s 400m IM. Ye hasn’t looked nearly the same since but did win the Chinese 200m IM earlier this month.
46. The Australians. They underperformed in London but re-emerged at last year’s World Championships. Emily Seebohm is Franklin’s biggest rival in the backstrokes. Mitch Larkin could keep the U.S. from sweeping the men’s backstrokes for a sixth straight Games.
47. The athletes who won’t be at the Olympics. The list is already long, including Brazil’s favorite Olympic champion. Swimmer Cesar Cielo failed to qualify at the host nation’s Olympic Trials.
48. The U.S.’ pursuit of a first archery gold medal in 20 years. Brady Ellison and Mackenzie Brown are ranked in the world top five.
49. Legendary Japanese wrestlers Kaori Icho and Saori Yoshida each seeking a fourth straight Olympic title.
50. A failed dive going viral.
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51. China’s quest to sweep the diving golds. Seven of eight in Beijing. Six of eight in London.
52. David Boudia‘s quest to spoil China’s goal. He beat Qiu Bo by 1.8 points in London but took silver behind Qiu at the last three Worlds.
53. Bradley Wiggins bids farewell to the Olympics in the velodrome. Mark Cavendish could, too.
54. What the medals will look like. They haven’t been unveiled yet.
55. The Olympic slogan. Also not yet announced.
56. The Olympic cauldron. It will be lit in the Maracanã on Aug. 5. Then the flame will be moved into the city (hopefully not by Wayne Gretzky in a pickup truck) during the Games.
57. The Olympic torch relay. Sochi’s included a trip to the North Pole, outer space and into Lake Baikal. This year’s hasn’t left Greece yet, but there is a Twitter account.
58. Kohei Uchimura. He is arguably the greatest gymnast of all time with six World all-around titles and the 2012 Olympic all-around gold. The Olympic team title is the only box left to check off. He and Japan came up short to China in 2008 and 2012.
59. The end of the Martha Karolyi era. The U.S. women’s gymnastics team is poised to dominate in Rio, the final Games with its matriarch as national team coordinator.
60. The comebacks of Gabby Douglas and Aly Raisman. Just getting to the Olympics will be an accomplishment. But at the Games, Douglas is expected to be the closest challenger to Simone Biles. Raisman also wants to make the all-around final, but only two per country can qualify.
62. Ibtihaj Muhammad, the first U.S. athlete to compete in the Olympics in a hijab.
63. Who follows Muhammad’s teammate, Mariel Zagunis, as the Opening Ceremony flag bearer.
64. Jordan Spieth realizing his dream of walking in the Opening Ceremony.
65. Gary Player maybe walking in the Opening Ceremony at age 80 and 60 years after he met Jesse Owens at the Olympics.
66. Field hockey and handball dynasties: The German men and Dutch women eye third straight Olympic field hockey titles. The only three-peat previously was achieved by the Indian men in 1948, 1952 and 1956. The French men and Norwegian women eye third straight Olympic handball titles. The only three-peat previously was achieved by the Danish women in 1996, 2000 and 2004.
67. In rowing, the U.S. women’s eight crew — almost entirely new from four years ago — seeks an 11th straight global title.
68. An emotional sailing story. Dave Hughes, who coached the late Trevor Moore at London 2012, qualified with 2008 and 2012 Olympian Stu McNay to be the U.S.’ 470 sailors in Rio.
69. The sailing venue of Guanabara Bay. There have been mixed reviews about the state of the water there, but U.S. Sailing has said it’s satisfied that it can hold an Olympic regatta.
70. Justin Gatlin‘s chase of Usain Bolt. Gatlin has been faster than Bolt the last two years, except for the World Championships 100m final last Aug. 23, when he surrendered victory by .01 in the final few strides.
71. Trayvon Bromell, 20, and Andre De Grasse, 21, shared bronze in that Worlds final and are chasing the aging Gatlin and Bolt.
72. Allyson Felix attempting a Michael Johnson-like double.
73. The multi events in track and field — Ashton Eaton and Jessica Ennis-Hill attempt to defend their titles. Eaton will be cheering against Ennis-Hill, because his wife, Canadian Brianne Theisen-Eaton, is a gold-medal heptathlon contender.
74. What event(s) Galen Rupp will contest.
75. Aries Merritt‘s return from a Sept. 1 kidney transplant to try and defend his 110m hurdles gold.
76. Ethiopian Genzebe Dibaba, arguably the most electric women’s track and field athlete. She may go for a 1500m-5000m double.
77. The U.S. track and field and swimming teams looking to rebound from underwhelming 2015 World Championships medal totals.
78. Kim Rhode going for a shooting medal on a fifth different continent.
79. Russian synchronized swimmers Svetlana Romashina and Natalia Ishchenko can tie the sport’s record of five gold medals.
80. Table tennis player Melissa Tapper, the first Australian to qualify for the Olympics and the Paralympics.
81. One more Olympic taekwondo tournament with a Lopez family member. Steven Lopez, a 2000 and 2004 gold medalist, qualified for his fifth Olympic team. He is the only Lopez sibling competing in Rio. He was joined on previous Olympic teams by brother Mark and sister Diana.
82. Caster Semenya, of the 2009 gender-testing controversy, potentially racing the 400m — against Allyson Felix. Semenya clocked a personal-best 50.74 on April 16. Felix won her World title in 49.26.
83. Brit Mo Farah seeking another 5000m-10,000m double, but this time not in front of the home crowd.
84. A star sprinter false starting out of the Olympics. Or a star sprint relay team dropping the baton.
85. Randall Cunningham in the stands at the track and field competition.
86. German Paralympic long jump champion Markus Rehm‘s bid to be allowed to compete in the Olympics.
87. Can Iran’s Behdad Salimi, the reigning World’s Strongest Man, come back from a fall ACL tear in weightlifting’s super heavyweight division?
88. Jordan Burroughs brings his 124-2 senior record, boastful Twitter handle (@alliseeisgold) and vicious double-leg takedown to the wrestling mat.
90. Neymar leading Brazil’s Olympic soccer team, seeking the nation’s first Olympic title in the sport after five World Cup crowns.
91. The last-place finisher in the marathon on the final day of the Games.
92. The U.S. men’s and women’s basketball team’s biggest blowout victories.
93. The best uniforms of the Opening Ceremony — Bermuda’s shorts will be fashionable.
94. 40-year-old gymnast Oksana Chusovitina, whose World Championships debut came as a member of the Soviet Union.
95. The U.S. men’s gymnastics team’s pursuit of China and Japan. The London team event was a disaster, but if healthy the U.S. is a medal threat. Great Britain may push them off the podium again, though.
96. U.S. Olympic moms — among them are Kerri Walsh Jennings, Dana Vollmer, Kim Rhode and Kristin Armstrong, all gold medalists seeking Games returns.
97. No headgear in men’s boxing.
98. Dong Dong.
100. The Rio Paralympics beginning Sept. 7 with record coverage from NBC Sports and TeamUSA.org.
NBC Olympic research contributed to this post.