The speaker is in a cemetery, seeing magpies for the first time ("So those are magpies!") and half-joking about how greedy they look. The title echoes the old counting rhyme about magpies, and the ending plays on it: instead of reaching two or three, the speaker counts "one, one, one." Each bird seems alone, and each stands for sorrow.
The tone starts light and wry. The birds hover like "eyebrows / or second thoughts," and they fly off when the camera comes up, which the speaker takes as proof they're alive, not spirits. Then the humor darkens. The speaker says they share the birds' "mission: to rob the dead," which suggests a guilty awareness of taking something from this place, perhaps memories or images. The graveyard is called a "refuge," yet even the weed eater "keens." The magpies' chatter is a small relief, though the speaker notes they're said to grieve too. The final line lands quietly: grief here is solitary, and no counting makes it feel like joy.