If ever a single didn’t cry out for a Diddy guest verse it’s Cassie’s hauntingly self-contained “Me & U.” On the blessedly Diddyless album version, a threatening synth-cello and Cassie’s eerily detached vocals conspire to create a counterintuitive seduction soundtrack purged of all erotic heat. The model turned diva from Connecticut is as coolly imperious on “Long Way 2 Go,” brushing away a would-be lover like dirt off her shoulder. The temperature gradually rises — “Ditto” pairs OMD-style plink-plonk keyboards with a playful, talk-to-the-hand chorus, while “What Do U Want” sounds like the Go-Go’s gone R&B — but neither Cassie’s perspiration-free charisma nor producer Ryan Leslie’s curveball beats falter. Even the 35-minute running time indicates a rare self-control that makes this the most consistently arresting R&B debut since Kelis’s.

Download: “Me & U,” “Long Way 2 Go,” “Ditto”