I don't get why people keep saying that only the first 4 seasons of that show were good. I thought that season 3 was one of the weakest seasons (Everything involving Miguel was meh imo), and yeah, the last season was just garbage. But I personally loved season 5.
Fair enough. I'll give you this - season 6 was somewhere between 'garbage' and 'meh' until they revealed that the professor was in the younger guy's head, and that the younger guy was the real killer. And even then, the season was only so-so.