This dumb, naughty comedy stars Robinson as an ex-burlesque comedian who stumbles into his neighbor's time machine and ends up back in the title year. There, he is seized by unfriendly cavemen and sentenced to death by the king. Luckily, the queen saves him, but he gets into trouble again
by trying to seduce an "untouchable" maiden. Soon, a farce-like trial begins, the proceedings reminding Robinson of the vaudeville routines he once performed. Robinson redeems himself and rises to be the new king, but by accident he falls into the time machine and is transported back to present
day America--a time and place that make him desperately try to get back to 50,000 B.C.