Wicked Science: Catch Me If You Can. Jack sets Toby up on a date with his sister - purely to get him out of the way while he breaks into his shed and steals one of his inventions. Meanwhile Elizabeth creates an invisibility device purely to spy on Toby... This is an okay episode. The developing problem with Jack continues to be interesting, but the Toby/Nikki thing rather less so. And while invisible Elizabeth messing with Toby on his date is amusing, this plot device does mean we get rather too little of Bridget in this one for my taste...
