[4] He embarked on his career with the exhibition Den gådefulde by (The Enigmatic City) at Copenhagen's Galleri Gari in 1988, simultaneously publishing the series in book form.
The black-and-white photographs, taken with a large-format camera, cover the city's parks, cemeteries and areas around museums and monuments.
[5] One of the most precise characterizations of Bak Jensen is an article by Poul Erik Tøjner titled "Metaphysical realism".
Tøjner explains how Bak Jensen removed realism by revealing the unreal at the centre of everyday life.
By choosing places and themes that are not normally considered interesting, he points to qualities in life we often ignore, for example the outlying areas of the city on Amager, Copenhagen street scenes in Den gådefulde by (The Enigmatic City), or industrial sites and motorways in Fotografi some ritual (Photography as a Ritual).