Written and produced by Heap, the a cappella folktronica ballad heavily uses the harmonizer and describes painfully losing someone due to a breakup or a divorce.

The song's bridge was notably sampled in American singer Jason Derulo's 2009 debut single "Whatcha Say", which topped the Billboard Hot 100 chart.

Although she was frequently told during recording that "something was missing" from it, she decided to release it after sending it to a friend who called it "genius" and "the most amazing thing he had ever heard".

Writing for The New York Times, Laura Sinagra wrote that "Hide and Seek" was "the ghostly pièce de résistance" of Speak for Yourself, adding that the song "suggest[s] a kind of lovesick cyborg alienation, an almost disembodied, distinctly modern malaise".

[5] Sophie Heawood of The Guardian referred to the song as "extraordinary", describing its use of vocal layering as "startling" albeit with a "Marmite-style love-or-hate effect on listeners".

[9] For Pitchfork, David Raposa identified "Hide and Seek" as the "black sheep" of Speak for Yourself, writing, "It's gorgeous, it's impressive, it's grandiose, and it's barely there at all — just Heap's voice darting and divebombing, making itself scarce, disappearing into itself.

Whether heard via a choice sync by a music supervisor or a chance encounter over a streaming service, the song lingers for days or even years.

[14] Matt Moen of Paper referred to "Hide and Seek" as "Heap's greatest hit" which "not only has paved the way for the judicious use of the vocoder as an emotional vocal treatment in today's top 40 but has been objectively one of the strangest songs to weave its way into our cultural fabric.

[15] For The Ringer, Lindsay Zoladz wrote, "Imogen Heap rarely gets credit for the ripple effects that 'Hide and Seek' sent through the pop mainstream," adding that the song was "indebted" to Laurie Anderson's "O Superman" and Daft Punk's 2001 album Discovery.

Directed by Joel Peissig, it features Heap singing in a dark windy set, in front of a breathing wall of back light.

[33] British band Amber Run released a cover of the song [34] "Hide and Seek" gained immense popularity after being featured during the climax of the 2005 season two finale of The O.C..[4] After director Norman Buckley was given a copy of Speak for Yourself by music supervisor Alexandra Patsavas, Buckley suggested to creator Josh Schwartz that he listen to the album early on in the season.

[36] The use of the song in the episode received praise from critics: Vulture's Lindsey Weber called it "the most obviously important" musical moment on the show, while Celina Torrijos of Much stated, "Most fans of the show...will cite the scene where Marissa shoots Trey to Imogen Heap’s "Hide And Seek" as the most memorable music moment of the series.

[41] Lindsay Zoladz of The Ringer called it "arguably the most absurd and melodramatic shooting scene in the history of televisual media" and "stupid and ridiculous and somehow (largely due to the song) genuinely, deeply moving";[16] Metro's Emma Kelly wrote that it was "the most memorable track from a series known for its music".

[42] The scene was later parodied in a 2007 Saturday Night Live digital short created by American comedy trio The Lonely Island called The Shooting, which also featured the song.

and Saturday Night Live, the song was included in the second episode by director Lenny Abrahamson during a montage of the two main characters, Marianne and Connell.

[7] "Hide and Seek" was also adapted to be featured in the West End and Broadway productions of the 2016 play Harry Potter and the Cursed Child, for which Heap wrote the music.