2.20. Joe wants to go home, but he can't go home because the man in the mask is waiting for him. (AL wording)

2.20 answer: A baseball game is going on. The base-runner sees the catcher waiting at home plate with the ball, and so decides to stay at third base to avoid being tagged out.

2.20 variant answer: Joe's in the hospital. He can't go home, because the man in the mask is a surgeon waiting to remove his appendix. (FF)

2.20 variant answer: Joe is a bee; the man in the mask is a beekeeper.

2.20a. Variant wording: Johnny is afraid to go home because of the man in the mask. (DW)

2.20a answer: Same. The diminutive "Johnny" makes it sound like he's a little kid, nicely further obfuscating the issue.

2.20b. Variant: Two men are in a field. One is wearing a mask. The other man is running towards him to avoid him.

2.20b answer: The same, but the catcher isn't right at home plate; the runner is trying to get home before the catcher can. (from Hal Lowery, by way of Chris Riley) This phrasing would allow the puzzle to migrate to section 1, but I don't like it as much.

2.20c. Variant wording: Instead of "home," say the man in the mask is standing on the corner.

2.20c answer: Same.