Plot: Pack up the beakers and Bunsen burners, stop worrying about atomic weight and absolute temperature – it’s time for “The Nerdist“ on BBC America! Tonight, Chris Hardwick welcomes heartthrob Jon Hamm from “Mad Men,” and the very talented Betsy Brandt from “Breaking Bad. ” Join us as Matt and Jonah attempt to write a mash up script of both their shows, and enlist a little surprise help from “Mad Men” actor Rich Sommer – aka Harry Crane – to give it that extra oomph! All this plus comedian Rory Scovel and “Doctor Who” alum, Arthur Darvill, joins the fun tonight, on “The Nerdist