Under a cloud of secrecy, Mad Men creator Matthew Weiner has been developing a new half-hour mystery dramedy series at FX, according to multiple reports. Plot details are, appropriately, being kept a mystery, but Weiner will write and direct as well as executive produce the untitled series, which hails from FX Productions. I wish we had more to go on than that, but it'll take some serious sleuthing, as Weiner is notorious for keeping a tight lid on things, though Variety broke this intriguing piece of news. [caption id="attachment_600533" align="alignright" width="360"] Image via AMC[/caption] …