"Being Serena" the five-part documentary miniseries on the life of WTA Legend Serena Williams, debuted with a riveting episode on Wednesday night on HBO, beginning an in-depth examination of the 23-time Grand Slam champion's current life, using the present to reflect the past and amplify the future.

The premiere episode, subtitled "Part One: Fear" opens with one of the most dizzying moments of the former top-ranked player's career: discovering she was pregnant while she was preparing for the first 2017 Australian Open.

"I was in Melbourne, Australia, and I dreamt that I was pregnant," says Serena. "And I woke up in the middle of the dream, and it felt so real. I thought, 'The chances are like zero, it’s just impossible right now.'

"So, I took the pregnancy test, and I actually didn’t check it until a couple hours later, because I just forgot about it," the long-time World No.1 continued. "When I saw that it was positive, I was like, 'Oh my God, this is crazy. I was starting a Grand Slam, and I was like, 'How am I gonna get through this?'"

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But Serena famously plowed through the event, winning her 23rd Grand Slam singles title over her celebrated sister, Venus. "We got clearance from the doctor, who said, 'Look, as long as you’re staying hydrated and you’re sort of listening to your body, you should be fine,'" Alexis Ohanian, Serena's husband, says in the episode. "At the end of the day, we made the decision to play through it.

"Deep down, I know the reason she didn’t drop a single set in [the] Australian Open is because she wanted to get off the court as soon as possible," Ohanian continued. "She was looking out for the baby."

A beaming Venus counters that "I’d like to think that it was unfair, because it was two against one, and I want a rematch," with a hearty laugh. "Obviously she played amazing, and we can always tell the baby, like, ‘You were in that final too, your first Grand Slam!'"

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From then on, the episode delves into the goings-on of the final three months of Serena's pregnancy, ranging from keeping up with her high-level athletic training to preparing the baby's bedroom, where they put Serena's 2017 Australian Open trophy so her child "know[s] that having her in my body didn’t stop me from succeeding, from winning."

Moreover, Serena often discusses her apprehension while facing this new, unexpected challenge. "I’ve always wanted to start a family, I’ve always envisioned myself as a mom," says Serena. "But it happened so unexpectedly. So now, becoming a mom, I definitely feel the pressure. And I feel a little anxiety, because I don’t know: ‘Am I going to be a good mom? Am I going to be a strict mom? Am I going to be not strict enough?’ I don’t really know."

"So that anxiety has turned into a little bit of nervousness and fear," she continues. "I’m really hesitant. I guess it’s the same attitude I have in tennis: I want to make sure that I’m the best and good enough.”

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The episode reaches its climax as Serena goes to have her labor induced, and she is ambivalent about whether she should feel afraid or not. "But the more I think about it, fear has always been valuable in my life," says Serena. "Without fear, without doubt, without discomfort in what we’re doing, what is there for any of us to overcome?"

Serena also discusses how her upbringing in Compton was formative in how she dealt with fear in order to thrive. "I had to worry about all kinds of things growing up: gangs, robberies, murders, gunshots right outside our door. There was a lot to be afraid of. There was a lot to run away from. But ultimately, that fear drove us forward. We never stopped trying to win, and we never stopped trying to grow."

The episode ends with Serena having to utilize all of the lessons she's learned throughout her life while dealing with fear, as the baby's vital signs dip during Serena's contractions, and the medical professionals recommend a caesarean section, despite Serena's history of blood clots making any surgery a risky proposition.

"One minute, everything’s going according to plan, and then, I’m being wheeled off for surgery," Serena says. "I was terrified, and it was a whole new kind of fear. Tennis -- I don’t think it ever felt so far away. And I don’t think my life ever felt so unsure." 

"Being Serena" airs every Wednesday night on HBO and HBO Go.