The biggest shock I’ve had in a long time from watching a television show came the other night, a few minutes into the season finale of Rescue Me, Denis Leary’s witty and gritty drama about New York City firefighters. There is a big spoiler coming, so if you have not yet seen this episode, stop reading now (but please come back after you’ve watched it and most likely been shocked yourself).

In the previous episode, Kenny, Ladder Company 62′s overweight member with heart problems, had a lot of trouble breathing in a burning building as the crew were making their way out. He almost collapsed, and the other guys had to help him, slowing their progress. Tommy Gavin’s nephew Damien, a “probey” who has been struggling with whether or not to remain a firefighter, had gone ahead of the others.

He subsequently ran back to tell them to hurry up and get out. Just then, a large wall collapsed on top of his head.

The assumption viewers were supposed to take away from this — reinforced by the coming attractions after the show — was that Damien had been killed. When the finale starts, we see Sheila, Damien’s mother and Tommy’s erstwhile lover, in her bedroom apparently trying to deal with her grief over her son’s demise. When she walks into her kitchen, we are surprised to see Tommy there. He had promised Janet, his wife with whom he is negotiating a reconciliation of sorts, not to see Sheila again. And we had a clear sense that this time Tommy really meant it.

But that wasn’t the shock. After Sheila has a few words with Tommy, the camera pans back, and Sheila takes several steps across the room. Then we see Damien, crippled and apparently severely brain-damaged, sitting in a wheelchair. My first thought, knowing Tommy’s predilection for speaking with the dead, was that Sheila had somehow caught Tommy’s fever and was communicating with her son’s ghost. But then it hit me, and my heart actually thumped, that Damien was alive, if you can call his diminished condition really living. This was one of the best TV moments of the summer.

Now Tommy Gavin is in a real pickle. He had promised Janet to focus more on his immediate family, her and their two daughters, one of whom is — like Tommy — a recovering alcoholic. But Tommy’s guilt over his role in convincing Damien to become a firefighter in the first place has grown exponentially and has cemented him to his nephew and, by extension, Sheila. Where all this is taking Tommy in his excruciating journey through the emotional fires of his complicated life remains to be seen next year in the program’s last season on the FX channel. According to Wikipedia, “The [series] finale is expected to coincide with the 10th anniversary of 9/11.”