St. Louis Premium Outlets will host the Backstoppalooza Car Show on Saturday, May 18 from 10:30 a.m. to 5 p.m., along with the City of Chesterfield and the Chesterfield Police Department. Guests can experience police cars, firetrucks and other emergency vehicles on display, while enjoying delicious food from local vendors, music and a K9 expo. Event registration is $20 in advance and $25 at the door and is available through the online entry form. Day-of registration will take place at 10:30 a.m. on May 18 with an awards ceremony at 4 p.m.