"Mad World" was originally written on acoustic guitar when Orzabal was 19 after being inspired to write a new wave song in the vein of Duran Duran's "Girls on Film". After a few false starts with Orzabal on vocals, he suggested Smith sing it and "suddenly it sounded fabulous".[7]
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The song was influenced by the theories of Arthur Janov, author of The Primal Scream.[11] The lyric "the dreams in which I'm dying are the best I've ever had" suggests that dreams of intense experiences such as death will be the best at releasing tension.[12]
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The promotional video for "Mad World" was filmed in late summer 1982, in the grounds of Knebworth House.[14] It was Tears for Fears' first music video, and features Curt Smith staring out of a window while Roland Orzabal dances outside on a lakeside jetty. A brief party scene in the video features friends and family of the band, including Smith's mother as well as his then-wife Lynne.
According to Curt Smith, "When we made the video in a country estate on the cheap, we bussed all our friends and family up from Bath and had a fun day. The woman who's having the birthday party in the video is my mum."[15]
https://en.wikipedia.org/wiki/Mad_World
Its the best version of the song, even if it didn't got into the movie. That said, Donnie Darko had a point in slowing down the tempo... it is indeed slightly too fast for the song. On the other hand, Tears killed it by incorporating the brass the way they did.