"a series called" vs. "this series called": what's the difference between the determiners?
You can use either but if you say 'this', that usually implies you want to add more details about it, emphasizing that it's special and unique (though sometimes emphasizing that you are unimpressed, it depends on how it's said).
Use of this... in place of a... serves to make a remark offhand or casual. You wouldn't use it in formal writing or speaking.