Pete Davidson is playing Nathan Fillion’s half-brother on 'The Rookie'

The face-off for nicest man in Hollywood is on—or at least it is if Nathan Fillion is to be believed. The former Castle star revealed in a new interview that after working with Pete Davidson in The Suicide Squad (next year’s confusingly named Suicide Squad sequel), he was so impressed that he had the 26-year-old come out and do a guest-star stint on his current show, The Rookie.Fillion made the big reveal in an interview with Jessica Shaw on SiriusXM’s EW Live on February 19, saying that he felt so good about Davidson after their first experience working together that he had him play his half-brother on the series.“We had him come down and do an episode of The Rookie, he plays my half-brother. My miscreant, ne’er do well half-brother,” Fillion said in the video interview. “One’s a cop, one’s a pain in the ass—and now they’re half-brothers. It’s amazing.”Fillion also revealed that he had totally misjudged Davidson in the past. Whether it’s the guy’s very public dating history, his characters on Saturday Night Live, or his perceived persona in general that had Fillion thrown is unclear, but what the older actor does know is that he may have a run for his money in terms of being the nicest guy in the biz.