There was, in fact, a disquieting suspicion at headquarters that an attempt might be made to blow up one of the magazines; the detachments of soldiers on duty had therefore been strengthened and the officers in charge had been instructed to exercise the greatest vigilance.
When Captain Ugo went out of his door as usual, with Pica at his heels, the night was dark and it was just beginning to rain.

The two went directly from the little house to the gate of the enclosure, and Ugo answered the sentry's challenge mechanically and walked briskly along the straight wall to the corner.

Turning to the right then, he was following the next stretch at a good pace when he stumbled and nearly fell over something that lay in his path.

As Pica held up the lantern close behind him, a man sprang up from the ground, where he must have been lying asleep, probably in liquor.

By the uncertain light and in the rain, Ugo saw only the blurred vision of an individual in a ragged and dripping overcoat, with an ugly, blotched face and a ruined hat.
An instant later, and just as Ugo was challenging the man, two shots were fired.