'At the time the murder was committed, I was travelling on the 8 o'clock train to London,' said the man. 'Do you always catch such an early train?' asked the inspector. 'Of course I do,' answered the man. 'I must be at work at 10 o'clock. My employer will confirm that I was there on time.' 'Would a later train get you to work on time?' asked the inspector. 'I suppose it would, but I never catch a later train.' 'At what time did you arrive at the station?' 'At ten to eight. I bought a paper and waited for the train.' 'And you didn't notice anything unusual?' 'Of course not.' 'I suggest,' said the inspector, 'that you are not telling the truth. I suggest that you did not catch the 8 o'clock train, but that you caught the 8.25 which would still get you to work on time. You see, on the morning of the murder, the 8 o'clock train did not run at all. It broke down at Ferngreen station and was taken off the line.'