It's happened a few times before and this month it's happening again - almost every over-the-air TV station in Canada and the U.S. airing the exact same show at the exact same time. 

It's a special annual fundraiser called "Stand Up To Cancer" and on Saturday, Aug. 19th at 8 PM, it will appear on CBC, CTV, Global, City TV, Yes TV, NBC, ABC, Fox and CBS (although Buffalo's Channel 4 will delay it until 11:35 PM because of a Buffalo Bills game.) Only TVO, PBS and the CW are taking a pass.

Several cable stations will also air the special, as are a number of streaming services. In all, some 50+ broadcasters are pausing their regular schedules to take the show.  

It is a Saturday, the lowest HUT (homes using television) night of the week, and in the dead of summer, so they're not sacrificng much, but it's nice to see a one-hour telethon-type program for a good cause getting this much exposure. It's certainly the only time of the entire season that all these networks are all programming the exact same show. It's the 19th year for the charity event, which has been steadily growing in exposure.

Stand Up to Cancer Sets Fundraising Special With Elizabeth Banks, Julianne Moore and Don Cheadle