- "If we live through this, I'll follow you anywhere, woman."
- ―Garrett to Kate.[src]
Kate and Garrett are two vampires who meet when the Cullen family asks for their help. It does not take long before they fall in love with each other, and Garrett joins the Denali coven to follow her.
- "Anyone who tries to touch me drops like a human that's been Tasered. It only downs them for a second, but that's long enough."
Kate is a core member of the Denali coven with the ability to create an electric-like jolt on anyone who touches her. She, her adopted mother, Sasha, and her adopted sisters, Tanya and Irina, were originated from Slovakia. Their greatest devastation was the death of their mother, who was executed by the Volturi for the crime of creating an immortal child. To dull the pain of loss, she and her sisters courted countless men, but ultimately killed every one for their blood. They actually grew fond of some of them and tried to kill less often, but despite their effort, their courtships always ended in killing their male counterparts, which is why she was excited when Tanya told her and Irina about her discovery of living on animal blood to improve their self-control. Kate and her sisters then spent centuries developing their control and by the time they met Carlisle's family, they had all become as good at vegetarianism as they. Kate was thrilled by never having to kill her men again, but she never found her true match until she met the adventurous vampire, Garrett.
- "You are an amazing woman."
- ―Garrett to Kate.[src]
Garrett is an adventurous vampire who was a soldier during the American Revolution. He was changed accidentally by a feeding vampire that took advantage of the war's death toll; he was only spared because the vampire was satiated and did not drain him completely. After becoming a vampire himself, Garrett's quest to understand what had happened to him turned into a permanent characteristic, and he wandered the world alone, seeking mysteries to investigate and things to explore.
When the Cullen family is in great distress caused by the arrival of the Volturi in Breaking Dawn, they look for their friends throughout America, Europe, and Africa in hopes of assistance. Kate, a member of the Denali coven - a vegetarian vampire coven - and Garrett, a nomadic vampire, come to Forks to help them testify against the Volturi about a deadly misunderstanding. During their time together, Garrett befriends the Denalis very quickly, as he finds their way of life interesting, constantly questioning them on it. He even tries animal blood out of curiosity even though he drinks human blood. He finds it difficult and Bella witnesses him and Kate, home alone, playfully arguing about drinking animal blood. The two become infatuated with each other very quickly. Garrett even asks Kate about her power, and she hustles him into testing it. He does, out of curiosity, and is sent to the ground, calling it "something."
Before the confrontation, Garrett slides one step closer to Kate, showing he is very protective of her. Bella hears Garrett telling Kate he will follow her anywhere if they survive. When the Volturi kill Kate's sister Irina in an attempt to provoke a fight, Garrett holds Kate back to save her life, knowing that she wouldn't survive if she attacked Caius who was guarded by the entire Volturi. He suffers through her shocks to save her, until Bella takes her shield off of Kate and Zafrina blinds her. He calls her "Katie" and teases her lightly on her not being able to hurt him. He comforts her over the loss of her sister while the confrontation continues. After they survive the Volturi confrontation, Bella sees Garrett picking up Kate and spinning her around in a circle.
At the end of Breaking Dawn, Garrett joins the Denali coven as Kate's mate, and Bella states that he'll probably be there "from now on." However, challenges will be coming for this couple: Garrett will learn to adapt to vampire vegetarianism while Kate will attempt monogamy for the first time in her life.