Photo: Nancy Stone / Chicago Tribune 

Crews working on Transformers 4 filming a scene at Cloud Gate, also known as "The Bean" in Millennium Park.

In case you haven't noticed the recent uptick in low-flying helicopters and fiery sports cars around Chicago, allow us to fill you in: Action director Michael Bay has returned to the city for production on Transformers 4: Age of Extinction. 

People who have caught a glimpse of the production say there are Dinobots on the scene. And apparently Marky Mark is in town.

So people are, as one Subreddit reveals, very, very excited.

Though Bay and his crew have already transformed (!) several Chicago landmarks (Millennium Park, Uptown Theatre) into high-action film sets, production isn't set to wrap until October 6. The locations change every weekend—here's what's happening next, with updates to come as the info is made available.

September 7th and 8th, 7 a.m. to 10 p.m.: Filming (including helicopter work, vehicular stunts, and special effects) on LaSalle between Lake and Jackson, Randolph and Monroe between Clark and Wells, and, at various times (but never concurrently), Lake, Washington, Madison, Adams, and Jackson between Clark and Wells. 

September 7th and 8th, 7 a.m. to 9:30 a.m.: Low level aerial and helicopter work scheduled along LaSalle from Randolph to Jackson and around buildings bordering LaSalle and Clark from Lake to Jackson.

Update (9.20.13): The Chicago Film Office has confirmed that, weather permitting, Michael Bay will be blowing stuff up (or at least filming) at 2900 S. Damen this weekend. We're awaiting confirmation that there will be Dinobots on scene.

Update (9.27.13): In case you missed Bay's first attack on the Loop, Transformers is set to film live stunts and pyrotechnics from 7 p.m. tonight until 6 a.m. Monday morning at 111 S. Wacker. Filming will wrap for the entire film on October 6, so this may be your last chance to witness the light show.