There are multiple groups called The Unknown. 1) A post-punk/early alternative rock band from Baltimore, Maryland formed sometime in the 1980s. They released their first record, The Unknown, in 1987. The follow-up to this was Fall, released in 1990.
The band performed a reunion show in January of 2012. 2) The Unknown must be familiar to you by now, as the group has been producing its ultra-adrenalized, fun-packed, rainy-summer's-night thoughtful (s)punky powerPOP! for ten straight years.