Stephen Erlewine at AllMusic wrote that this album was the American Idol runner-up's attempt to reinvent himself after the failure of the movie From Justin to Kelly. The result is "loungey, Am-Idol-styled vocal jazz, but Stranger Things Have Happened is vocal jazz all the same...Guarini has genuine, natural charisma as a supper club-styled singer, and that charisma when contrasted with his band's jazz chops has a nice, relaxed appeal." Despite its weaknesses, the album was "a surprisingly successful reinvention."[1]
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