The Twilight zone

[CheapAndNerdy]

An ordinary day. An ordinary man. Let us call him Mr Smith. Mr Smith is currently heading out of London by train. He is in possession of (for reasons that we need not go into here) a Z1-3 travelcard and a Z4-6 travelcard. His train has just left Wembley Central (zone 3). Its next stop is Harrow and Wealdstone (zone 4). Without warning, a ticket inspector approaches Mr. Smith. Knowing that an incorrect response will result in a Penalty Fare, which ticket should Mr. Smith produce to satisfy his inquisitor?

 

[transportphoto]

Both.

 

[OwlMan]

His Oyster Card?

 

[CheapAndNerdy]

Both.

That would make sense. I wasn't sure what the answer was, but seeing as it was a largely hypothetical situation I decided to dress it up as a "quiz". Thanks tp for your terse reply, although maybe Rod Serling would have been somewhat more eloquent