Midway through Shadow and Bone, Alina discovers she has to let go of Mal in order to fully access her power as the Sun Summoner — but why? The answer lies in the original Shadow and Bone novel. Although most of the changes Netflix made to the story serve the television adaptation, in this case they leave a confusing plot hole.
Shadow and Bone, season 1, episode 4, "Otkazat'sya," shows Alina struggling to access her power. Although she can summon light, she isn't reaching her full potential. At the same time, she seems to be holding out hope that she'll be able to return to her former life. She awaits letters from childhood friend Mal with bated breath and is crushed when none arrive, believing he's abandoned her. It's only when Alina relinquishes her dreams of rescue, romance and a future with Mal that she's able to summon light consistently and powerfully.
In both the Shadow and Bone TV show and book, Alina's mental block can be traced back to a scar on her hand, a visible reminder of Mal. During the episode, it's revealed that Mal and Alina tried to dodge Grisha testing as children in order to avoid the risk of being separated. When Alina was eventually tested, she evaded detection by cutting her own palm, creating the scar that is seen repeatedly in the series. One of the biggest moments in Netflix's Shadow and Bone — which never happens in the books — is when Alina asks Genya to heal her scar, seemingly erasing Mal from her life forever. (Tragically, of course, Alina's decision comes just as Mal realizes he loves her and finds the stag that could reconnect them). While the show never fully explains this phenomenon — glossing over the connection between Alina's love of Mal and her ability to access her power — the Shadow and Bone book reveals an inextricable link between the two.
In the Shadow and Bone novel, Alina doesn't set out to deliberately fool the Grisha, but is able to avoid discovery by subconsciously repressing her own abilities. When tested, Alina feels something rise in her, but pushes it back down so she can stay with Mal. In the novel, their friendship is almost a survival mechanism. Before Mal, the Keramzin orphanage had been "place of terrors" for Alina. After Mal, it became, "our palace, our kingdom, and I wasn't afraid anymore," she says.
"But the Grisha Examiners would have taken me from Keramzin," she says. "They would have taken me away from Mal, and he had been the only good thing in my world. So I'd made my choice. I'd pushed my power down and held it there each day, with all my energy and will, without ever realizing it. I'd used up every bit of myself to keep that secret."
It's only when Alina finally gives up hope that she'll return to her old life — and moreover, that Mal will love her back — that her mental block dissolves. Pushed by Baghra and pressured by her circumstances, Alina decides to stop waiting for Mal. Once she does, she's able to open herself up to her power, discovering something that is wholly hers. Luckily, the separation between Mal and Alina doesn't last forever. Once Alina is able to access her power, a romantic relationship with Mal poses no threat to her abilities. When Mal shows up later in the novel to help her, Alina's hope and love for him is revived.
In the book, Alina's mental block also has significant effects on her physical health, something else Netflix includes but never really explains. In Shadow and Bone season 1, episode 6, "The Heart is an Arrow," Mal comments that Alina's appetite has grown since he's seen her last. She suggests her power is sustaining her and boosting her health and longevity. In the books, this is outright confirmed as Alina's lifelong ailments disappear after she accesses her power. She's finally able to sleep through the night and her appetite grows enormously. If Kirigan's power sustained him for thousands of years, it raises the question of how long will Alina live?