PSA's are a dime a dozen, but we wish there were even MORE!
If you watch TV, you probably watch NCIS. If you watch NCIS, then you know exactly who Mark Harmon is!
Instead of taking down the usual kind of bad guy, he's in a new public service announcement aimed at increasing awareness about cancer immunotherapy! In other words, the use of one's own immune system to fight cancer!
Stand Up 2 Cancer and the Cancer Research Institute are behind it, and have just debuted the PSA. Here's what Mark said: