Harry Weldon Kees was 41 when he was last seen in San Francisco on July 18, 1955. That day he spoke by telephone with friends about a possible job and asked memoirist Janet Richards for company; after those contacts he vanished. His 1954 Plymouth Savoy was found abandoned with the keys in the ignition on the Marin County side of the Golden Gate Bridge on July 19, 1955.

At his apartment investigators found mixed signals: his cat Lonesome was inside and a pair of red socks lay in the sink, yet his wallet, watch, sleeping bag and an $800 savings account book were missing and the account showed no activity after his disappearance. Friends recalled he had talked about taking his own life and once said he had tried to jump from the bridge before but could not go over the rail. Those facts led to the presumption he had jumped from the bridge, but his body was never recovered.

Kees had also told friends he was fascinated with Mexico and had discussed possibly moving there, so some have speculated he staged his disappearance to start a new life. The case remains officially unsolved. Did anyone who knew Weldon Kees or saw him in San Francisco or Marin County around July 18–19, 1955, ever report relevant details?