BOGOTA, COLOMBIA — Colombians have wanted to forget Pablo Escobar since his reign of terror in the 1980s.

But in what some are calling a form of catharsis, a Colombian television network is examining the darkest episode in the country’s tumultuous history with a true-life series about the flamboyant drug lord’s rise and fall.

“Pablo Escobar: Boss of Evil” is mesmerizing television viewers in this country of 46 million. But it is sparking a debate over whether the series does too much to humanize Escobar, who won legions of admirers by building homes for the poor but also blew up an airliner and coolly ordered the killings of thousands....