Final answer:
The offense in question is conspiracy, where two or more persons agree to commit a crime in the future. It is punishable even if the crime isn't actually carried out, emphasizing the legal importance of both intent and the outcome of actions.
Step-by-step explanation:
The offense being referred to in the student's question is likely conspiracy. Conspiracy is a criminal act that involves two or more persons agreeing to commit a crime at some point in the future. It is unique in that it is one of the few crimes that can be punished even if the actual crime agreed upon is not committed. For instance, terrorists planning an attack or someone hiring a hitman can be charged with conspiracy, based on their agreement and intent to commit a violent or unlawful act.
In legal systems, the intention behind an act, or mens rea, is a key component of many crimes, including conspiracy. However, the actual result of an act can also be critical in determining criminal responsibility. This concept is reflected in the hypothetical scenario involving hostages, a terrorist, and a would-be hero where moral evaluation might depend on both the intention behind and the result of the action taken.