When he was given the green light by his government to travel back in time to the dinosaurs’ era, he was so proud of being given the chance to eye-witness an event that beggared description that he forgot, under a state of confusion and bewilderment, to take with him the most essential device.
He forgot the coming back mechanism—a small box that sends signals to the time machine to teleport him back to his era—and was consequently stuck with the dinosaurs without the slightest chance of coming back to the twenty third century, but he kept hoping that the rescue team would show up any time until he realized, after some days of harsh survival, that the time machine, he invented, was holding a tricky device that would ruin its circuits after twenty four hours of his departure.