Subgroup Size
Entire group
Duration
20 minutes
External Cost
NoSource
Activity created by Sivasailam "Thiagi" Thiagarajan based on the short story "Sentry" by science fiction writer Frederic Brown:
Brown, F. (1954). Sentry. Galaxy Publishing Corporation.
A copy of the story is available in an archive of Thiagi's activities: http://thiagi.net/archive/www/pfp/IE4H/december2001.html#Fiction