Walk through Union Station, Chinatown and the Tenderloin in  San Francisco and although everything is in colour, the black and white world of Dashiell Hammett from the 1920s and 1930s remains vividly alive.

The author of The Maltese Falcon lived at 891 Post Street just a few blocks away from Burritt Alley and it’s where he had his private eye Sam Spade live in apartment #401. A Dashiell Hammett street is along the way from Burritt Alley to Post Street but this alleyway is worth a stop.

Look halfway up the concrete building at the edge of this grim and grimy alleyway off Bush Street and a sign marks its importance: “On approximately this spot Miles Archer, partner of Sam Spade was done in by Brigid O’Shaughnessy.”

Get there by heading off Union Square towards the blind end of Burritt Street just west of the overpass where Bush roofs Stockton Street.

Watch out for femme fatales.