Whitney Houston is posthumously getting the Glee treatment.

On Tuesday's all-new episode, the New Directions gang -- including Rachel (Lea Michele) and Mercedes (Amber Riley) -- will pay tribute to the late pop diva with an hour-long episode peppered with her greatest hits.

As the preview clip above shows, Houston's death hits Mercedes especially hard, and the high schooler turns her locker into a shrine for the late star.

Riley -- who covered "I Will Always Love You" on Glee's Valentine's Day episode and met Houston two days before her Feb. 11 death -- has long been moved by the diva's music.

"Whitney's music meant so very much to me. I was very very choked up when I heard about her passing," the actress told E! shortly after Houston's untimely death. "I've grown up listening to her voice ringing throughout our household. I'm so speechless. I can't believe that she passed."

Watch above as Riley, Michele and the other Gleeks honor Houston with an emotional cover of "How Will I Know" before the full episode airs Tuesday at 8 p.m. (EST) on FOX.