Recommendation for 20th Century overview

Hi. I’m new here and have never posted. My son (just out of college) has asked me for a recommendation on what to read about the 20th century. I have lots of suggestions for specific topics, but think he should start with an overview, because he has never really been interested in history until now.

Does anyone have a recommendation for a good overview? I’ve seen recommendations for Martin Gilbert’s concise version, but have also seen it contains factual errors.

Thanks!