Going head-to-head with his “Spider-Man: Homecoming” co-star Zendaya, Holland opened his routine with a fake-out “Singin’ in the Rain” bit before launching into Rihanna’s 2007 smash — wig, dress and tights included.

The SFPD said they detained a person, who matched the suspect’s description, a short distance from the stabbing incident. The suspect, identified as 29-year-old Sean Collins, was transported to the San Francisco County Jail, where he was booked for homicide, police said.