Malik’s function in the band was in some ways obscure or invisible. He didn’t write for the band often, and when he did he usually appeared among a galaxy of co-writers on the group’s most gelatinous ballads (Louis Tomlinson and Liam Payne are responsible for the majority of the group’s internal songwriting). His modesty and the economy of his expression gave him the reputation of the “quiet one” and the “mysterious one” among the boy band taxonomies. In the One Direction documentary, This Is Us, he features minimally compared to the rest of the group; when the band takes a break from their aggressive and interminable touring schedule, Malik is depicted in isolation, in a room he’s decorated entirely with graffiti. In another scene, he streams by the camera on a Segway. His smile seems to materialise slowly and almost imperceptibly across his face, composing itself atom by atom.

He’s also frankly gorgeous, all sculpted, glossy angles. When I look at the structure of his face I am reminded of a geometric prism, or the interior of a geode. These features were identifiable even early in their careers when the other four members appeared to be one elastic teenage face. His hair is also shapely, shimmering and kind of incandescently dark, as if permanently enhanced by a follow spot. Its styling never quite collapsed into the strange vertical animals emerging from the skulls of Tomlinson or Niall Horan. An enduring image of One Direction is of Malik in the Night Changes video, the soft and intricate cascade of his hair merging with a dense knot of spaghetti.

He was one of the more accomplished vocalists of the group, exhibiting the widest range. He mostly inhabited a silvery, full-bodied tenor, similar to but more sharp and precise than Harry Styles’ smoky warble. At one point in This Is Us, while on tour, he is extracted from sleep by songwriter/producer Julian Bunetta to record the bridge of Best Song Ever, into which Malik compressed a tenor and falsetto vocal. His solos, especially on the ballad You & I, could be dazzling, his voice moving with grace through impressive aerial designs, and he contributed body and dimension to the group’s choruses.

In most One Direction choruses, five voices of varying integrity collapse into a single, compact chord. It’s an arena rock aesthetic, treating harmonies as if they’re a system of collapsing stars; it gives the condensing voices a kind of internal velocity. It also makes One Direction songs near-impossible to simulate at karaoke without profound breath and pitch control. (I’ve tried. A lot.) I think this is the source of a lot of their appeal; their voices and the instrumentation, which is usually minimal guitar figures against fluorescent banks of synths, cause their songs feel like a form of glam rock that’s rushing at you in three dimensions.

The remaining members of One Direction have only performed a few concerts without Malik, so it’s hard to determine if his subtraction from the group creates an imbalance in the harmonic attack. But he leaves a void of personality, a void of vocal agility. Without him the group loses some of its distinctiveness and slowly morphs into four goofy white guys shouting. Regardless, in a video from their concert last night, after the bridge of You & I, Harry, Louis, Liam, and Niall stopped singing. The audience delivered Zayn’s solo.