double
Explanation
The Joke
A man exclaims "Oh my God, I'm being followed by a ghost!" and spots a glowing green figure behind him. He then recognizes it: "It's my doppelganger! A duplicate of me from the spirit realm or another dimension!" The doppelganger appears menacing, but then the scene reveals: "Unlike come to take my body? My God, wait — wait, he stopped to check his phone and also..." The final panel shows the man's ghostly double simply standing around checking its phone, with the caption "Do your job, doppelganger!" followed by "Soon."
The Humor
The comic sets up a classic horror premise — being stalked by a supernatural doppelganger from another dimension — and then deflates it entirely by having the doppelganger be just as distracted, lazy, and phone-addicted as a regular person. The sinister duplicate can't even be bothered to steal the protagonist's body because it's busy scrolling on its phone.
The punchline "Soon" suggests the doppelganger will eventually get around to its evil mission, but the implication is clear: even supernatural entities are afflicted by modern distraction and procrastination.
Broader Context
This comic plays with the universal experience of phone addiction and procrastination by applying it to a supernatural entity. SMBC often takes fantastical or sci-fi premises and grounds them with mundane human failings. The joke also works as a commentary on how modern technology has made everyone — even interdimensional body-snatchers — less effective at their jobs.