Crossroads (10pm, CMT) - Katy Perry and Kacey Musgraves perform together on this CMT series that pairs country musicians with musicians from other genres. This should be a good one.
Also on tonight . . .
Greta Investigates: O.J. Simpson (7pm, Fox News) - Greta Van Susteren, who became famous herself during the TV coverage of the OJ Simpson trial 20 years ago, looks back at the case and offers new insights into her 2004 interview Simpson. Van Susteren will be joined by Tom Lange, the lead detective on the case for the LAPD, and also Dr. Michael Baden, who led the forensic analysis for the defense.
Science of Stupid (9pm, National Geographic Channel) - Videos of bungled stunts collected from the Web are explained by scientific theory in this new series. In the opener, Hooke’s Law is used to explain a pogo-stick wipeout (they also explain the reason why pole dancers wear little clothing, but I’m not sure you need to be a scientist to figure that out . . .). At 9:30, a botched attempt to jump into a frozen pool is examined.
Treehouse Masters (10pm, Animal Planet) - Pete visits his former home, where he built his first two tree houses, with a plan to create an office space and multi-purpose room for the current owner -- a fast that involves fixing a rotting staircase, suspension bridge and support beams.
Continuum (10pm, Syfy) - A direct attack from Liber8 puts Kiera and John Doe in danger. At the same time, they confront the harsh realities of their relationship’s origins.