Who knew Tim Gunn had a temper? Fans rarely see him get flustered on “Project Runway,” but you can count on a spike in temperature on his new reality show, “Under the Gunn,” which premieres Thursday. ...

And though Christian Siriano's presence should be no surprise to anyone who watched the original series throughout the '00s — he previously won Season 4 and then came back as a mentor in Seasons 17-20 ...