Accord­ing to cin­e­ma lore, Edgar G. Ulmer’s Detour, a slap­dash, unpro­fes­sion­al $20,000 melo­dra­ma shot in a mere mis­take-filled six days, has some­how, over the past 66 years, accrued a siz­able and appre­cia­tive fol­low­ing among film noir enthu­si­asts. Except it turns out that, in real­i­ty, its bud­get prob­a­bly ran to some $117,000. And those six days might have actu­al­ly been three six-day weeks. And the Aus­tri­an-born Ulmer, who had not only worked for such Euro­pean lumi­nar­ies as F.W. Mur­nau, Bil­ly Wilder, and (so he claimed) Fritz Lang, but even made The Black Cat for Uni­ver­sal Pic­tures, hard­ly lacked pro­fes­sion­al bona fides. And the film’s care­ful use of sound and strik­ing use of light set it apart even from its brethren in the genre.

And speak­ing of that genre, a hearty crit­i­cal agree­ment now holds that Detour dis­tills, in its brief 68 min­utes, the most vital emo­tion­al and aes­thet­ic ele­ments of film noir in a way that none of its oth­er exem­plars have man­aged. And mis­takes? What mis­takes? As Roger Ebert wrote on ush­er­ing the film into his Great Movies canon, “Plac­ing style above com­mon sense is com­plete­ly con­sis­tent with Ulmer’s approach through­out the film.”

To recount Detour’s sto­ry here — a piano-play­er down on his luck; a sud­den death; a schem­ing, ven­omous dame — would be to miss the point. To cite out its many, er, uncon­ven­tion­al pro­duc­tion choic­es — nonex­is­tent back­grounds con­cealed with fog, shots sim­ply flipped over and re-used, stock footage meant to pad the run­time almost to fea­ture length, uncon­vinc­ing rear pro­jec­tion even by 1945’s stan­dards — would be to miss the point from anoth­er direc­tion. The film has fall­en into the pub­lic domain, so watch it free online and expe­ri­ence for your­self the way that, for all its appar­ent blunt­ness, it stealth­ily lodges itself in your sense mem­o­ry. To call a movie “dream­like” reeks of cliché, but Detour presents the ele­ments of film noir in such a pure, naked state that you have lit­tle choice but to accept them direct­ly, the way you would accept the “facts” of a dream. Though seem­ing­ly incom­pe­tent on all the lev­els sub­ject to con­scious analy­sis, the film oper­ates effec­tive­ly on all the lev­els beneath, hence the last­ing inspi­ra­tion it offers to cer­tain film­mak­ers today. Make Detour, if you can, a dou­ble-fea­ture with David Lynch’s Lost High­way, which plays almost like a straight trib­ute to Ulmer’s pic­ture. As a ded­i­cat­ed tran­scen­den­tal med­i­ta­tor with a fas­ci­na­tion for the dark side of Los Ange­les and a ten­den­cy to bend arche­typ­al char­ac­ters toward his often oblique but always vivid styl­is­tic will, Lynch has inter­nal­ized Detour’s lega­cy — intend­ed or oth­er­wise — more deeply than any oth­er film­mak­er alive today.

More noir clas­sics can be found in our col­lec­tion of 60+ Free Noir Films.

Col­in Mar­shall hosts and pro­duces Note­book on Cities and Cul­ture. Fol­low him on Twit­ter at @colinmarshall.