Baltimore (CNN) -- Erika Brannock, a survivor of the Boston Marathon bombing, anxiously purses her lips.
Her eyes jump and she is quick to smile and laugh.
This is what someone looks like waiting to meet the person, a stranger, who she believes saved her life.
"I told my cousin last night that it's kind of like the night before Christmas, where you're so excited, but nervous at the same time and you can't sleep," Brannock told CNN's AC360 on Wednesday.
Brannock is about to meet Amanda North, a woman who took her hand and did not let go.
The day of the marathon, the two women were standing near the finish line when the bombs went off.
North was there to watch her daughter run, while Brannock was supporting her mom.
Brannock was seriously injured. She suffered bone and tissue damage, eventually requiring the amputation of her lower left leg.
North was also injured. Like Brannock, her eardrums were busted.
She had cuts and lacerations on her leg. But in the immediate aftermath of the blast, North was unaware of her own injuries.
She just saw Brannock, who was clearly hurt more than she, and jumped in to help, offering her belt as a tourniquet for Brannock's leg.
"She had heard me screaming for help and she said, 'My name is Joan from California, and I'm not going to let you go.' And she stayed with me the whole time," Brannock recalled.
In the chaos of that moment, she heard Joan, rather than Amanda. North thought Brannock's name was Irene.
They'd laugh about the mix-up later.
On Monday, Brannock left a Boston hospital after 11 surgeries and 50 days -- the last of the more than 250 victims to be released.
She spoke to AC360, saying that she desperately wanted to find and thank the woman she knew then as Joan.
CNN put out the alert, creating an e-mail address for tips. Just hours after the show aired, one rolled in.
The subject line of the note was as simple as it was clear: "That's me."
North's friends had seen the AC360 segment and told her about the search. Family members also reached out.
CNN arranged to fly North, who lives in Woodside, California, to Baltimore, where Brannock is undergoing physical therapy at Kernan Hospital.
Like Brannock, North was a little anxious.
"In a way, she's a stranger to me, but when you share things like this you feel like you've known someone your entire life," she said. "So I'm looking forward to meeting her, but I'm a little nervous."
Moments later, raw emotion flowed.
North walked into a room where Brannock was waiting. Neither women said a word as they cried and embraced.
"I have thought about you every moment since the marathon," North said. "I didn't know how to get a hold of you. I didn't know what had happened to you."
Like old friends, they exchanged gifts.
Brannock gave North a necklace -- a dragonfly -- to match one she wears. The dragonfly has become a bit of a mascot for Brannock, who sees it as a symbol of strength and courage.
North gave Brannock her favorite scarf.
"I want you to just think of me whenever you wear this, know that I'm always there for you. It never goes away. We're friends for life," she said.
"I'm never going to stop holding your hand."
Randi Kaye and David Puente reported from Baltimore; Dana Ford wrote this report from Atlanta.
Watch Anderson Cooper 360° weeknights 10pm ET. For the latest from AC360° click here.