Murray has infamously been one of the lone holdouts whenever talk of doing a Ghostbusters sequel with the original cast arose. So quite a few people were surprised when he chose to film a cameo for the new Ghostbusters film which features a different cast (though maybe not that surprising since in the past he's endorsed an all female crew and named McCarthy and Wiig specifically)
“I thought about it for a very long time,” Murray said. “Like, many, many months. No, that’s not right. I was seriously thinking about this for years, really… It kept eating at me, and I really respect those girls. And then I started to feel like if I didn’t do this movie, maybe somebody would write a bad review or something, thinking there was some sort of disapproval [on my part].”
“You know, they were incredibly nice to ask me, and I really enjoyed being there,” Murray said. “They have such a jolly group, and they are going to have great success with this project. I didn’t want to overshadow [them] or anything, and I feel really good about it. I like those girls a lot. I mean, I really do. They are tough to say no to. And Paul is a real nice fellow.”
So they asked nicely, and he didn't want people thinking that he disapproved.
The movie is scheduled to come out July 15, 2016 in what is sure to be a packed summer.