ONE Championship puts on its 100th event, ONE: Century, this weekend, and it's pulling out all the stops. For the first time, the Singapore-based promotion will feature two separate cards for an event, one on Saturday night and the other on Sunday morning. 

Collectively featuring four title matches, three world grand prix finals and the return of top competitors like Demetrious Johnson, Brandon Vera, Giorgio Petrosyan and Angela and Christian Lee, this is shaping up to be ONE's most intriguing event yet.

While Johnson looks to become the No. 1 contender for ONE's flyweight title with a world grand prix victory, Angela Lee hopes to defend her atomweight crown in a highly anticipated rematch between her and women's strawweight champion Xiong Jing Nan. We'll also see a megafight between heavyweight champion Vera and two-division champion Aung La N Sang for the latter's light heavyweight belt.

Here is how to watch ONE: Century and four questions that will be answered.

Where and How to Watch

The event will be held at Ryogoku Kokugikan Arena in Tokyo, Japan.

ONE: Century is split into two cards. The first begins with preliminary matches on Saturday at 8 p.m. ET and the main card follows at 11 p.m. Those in the U.S. can watch the main card on TNT and both the main card and prelims on B/R Live. 

The second card begins its prelims on Oct. 13 at 4 a.m., with the main card following at 6:30 a.m. You can watch on B/R Live.

ONE: Century Part I Card—Oct. 12

Main Card: 11 p.m. ET on TNT and B/R Live

Xiong Jing Nan (c) vs. Angela Lee (atomweight world championship)

Demetrious Johnson vs. Danny Kingad (flyweight world grand prix final)

Janet Todd vs. Ekaterina Vandaryeva (muay thai)

Christian Lee vs. Saygid Arslanaliev (lightweight world grand prix final)

Preliminary Card: 8 p.m. ET on B/R Live

Yuya Wakamatsu vs. Dae Hwan Kim

Sam-A Gaiyanghadao vs. Daren Rolland (muay thai)

Yushin Okami vs. Agilan Thani

Itsuki Hirata vs. Rika Ishige

Senzo Ikeda vs. Lito Adiwang 

Phoe Thaw vs. Yoon Chang Min

Sunoto vs. Kwon Won Il

ONE: Century Part II Card—Oct. 13

Main Card: 6:30 a.m. ET on B/R Live

Aung La N Sang (c) vs. Brandon Vera (light heavyweight world championship)

Shinya Aoki vs. Honorio Banario 

Bibiano Fernandes (c) vs. Kevin Belingon (bantamweight world championship)

Rodtang Jitmuangnon (c) vs. Walter Goncalves (flyweight muay thai world championship)

Giorgio Petrosyan vs. Samy Sana (featherweight kickboxing world grand prix final, winner earns $1 million)

Mauro Cerilli vs. Arjan Bhullar

Preliminary Card: 4 a.m. ET on B/R Live

Mei Yamaguchi vs. Jenny Huang

Yosuke Saruta vs. Daichi Kitakata

Shoko Sato vs. Rafael Silva

Hernani Perpetuo vs. Hiroyuki Tetsuka

Koshi Matsumoto vs. Takasuke Kume

4 Burning Questions to Be Answered

Will Demetrious Johnson make it look easy against Danny Kingad?

Although he won his previous two matches at ONE, Johnson's victories weren't easy. Against Yuya Wakamatsu, "Mighty Mouse" was clipped in the eye by a powerful strike that forced him to rely on his grappling the remainder of the bout rather than try to go punch-for-punch with the powerful Japanese. 

Against Tatsumitsu Wada, Johnson was often kept in check by his opponent's much longer frame, which gave Wada a wrestling advantage at times. 

Although his next opponent, Danny Kingad, has also defeated Wakamatsu and Wada before, this matchup seems to fare Johnson better than his two previous bouts.

Kingad possesses neither knockout power nor a strong grappling arsenal, which doesn't bode well against someone of Johnson's ilk. One can only imagine what a world-class wrestler like Johnson can do against him when given the opportunity.

Kingad is a martial artist who gets the majority of his victories by decision, and that's a tough ask against an athlete as skilled and dynamic as the former UFC champion.

Can Angela Lee exorcise her demons at the most crucial time?

After beginning her career at ONE a perfect 9-0, atomweight champion Angela Lee has now lost back-to-back matches.

Her first defeat came last March against Xiong when the 23-year-old attempted to become the first two-division women's champion in ONE history. It didn't turn out the way she had hoped, as Xiong escaped a deep armbar from Lee in the fourth round and landed a nasty body shot in the fifth to retain her title. 

Now, Xiong is dropping down to atomweight in hopes of claiming the title Lee has held for over three years. A third straight loss for Lee would almost certainly put her out of the main event picture for the foreseeable future. To avoid that, she needs a win against Xiong, who would leave Tokyo as the indisputable top female athlete at ONE with another win over Lee. 

"She has to defend her belt and she's taking it very personally," Christian Lee, Angela's brother and training partner, told Bleacher Report. "There will be fireworks. It's more than the belt on the line for her. It's her legacy."

Is Christian Lee biting off more than he can chew?

The ONE lightweight champion did something rare for titleholders to do, taking a match on short notice ahead of ONE: Century. Although Christian Lee's belt won't be on the line, he'll still be gunning for a world grand prix championship after Eddie Alvarez pulled out of the tournament final with an injury. 

With just three weeks to prepare, Lee faces one of the most dangerous competitors at ONE in Saygid Arslanaliev. "Dagi" tends to not waste time against his opponents, as seven of his eight victories came in the first round and five of those within two minutes. The term "knockout artist" may still somehow be an understatement when describing him.

If Arslanaliev wins to become the No. 1 contender to Lee's lightweight title, giving him a wave of momentum heading into an eventual championship match sounds like a terrifying proposition. 

Lee has never been one to stray away from a match, but this seems like a really bold fight to pick without having a full training camp.

Is Brandon Vera or Aung La N Sang the most dominant big man in ONE history?

For the first time in ONE history, champions of the two highest weight classes square off when heavyweight Vera drops down a class to take on light heavyweight Sang.

As is expected with most heavier competitors, both of these men are brawlers looking for the knockout. Sang, who is also the middleweight champion, rides a six-match win streak into Sunday. Meanwhile, Vera's 4-0 since joining ONE in 2014 with all four finishes coming in the first round. 

It's a matchup of two of ONE's most popular athletes. Sang represents his home country of Myanmar—which honored him with his own statue last year—and Vera hails from the Philippines, where he's previously starred in television shows.

The winner of this bout earns the right to declare themselves ONE's most dominant big man.