Minutes before halftime, with the Bears ahead, 17-9, the fog crept on millions of little cat feet off the shores of Lake Michigan and over Soldier Field's south end zone, settling comfortably on the field and reducing the field of vision to, at most, 30 yards.
And suddenly, eerily, the game became nothing more than two teams bumping together in a cloud, in front of a sold-out crowd and a national television audience that could not see it.
"We had a timeout, a TV timeout or something," Eagles offensive tackle Ron Heller said, "and we were standing in the huddle, and I remember just hearing a loud roar and everybody in that end zone was standing up, and they were all pointing.
"I remember turning around, and you could see it coming over the end zone like a wave. I felt, wow, that's pretty neat, I thought it was a smoke bomb at first because we had one earlier in Phoenix.
"But it just kept coming. We ran a couple plays, and it kept coming. And within two or three plays, it reached us. I remember the feeling, it came right through you. You could feel the moisture."
It was, of course, the Fog Bowl, a divisional playoff game between the Bears and Eagles last Dec. 31. The Eagles lost, 20-12, ending their magical season.
Nine months later, those who participated in it, and are readying for this Monday night's rematch in Chicago, understand quite clearly that on that gloomy day off Lake Michigan, something quite special occurred. Something that likely never will happen again.
"I don't think it could happen again," Eagles tight end Keith Jackson said. "It's like lightning doesn't strike twice on the same tree. I don't think that fog is going to roll in to help them this time."
It was something that never will be forgotten. And never should be.
"Well, that's one that's going to go down in history," free safety Wes Hopkins said. "When you're 70 years old, you're definitely going to watch television on ESPN or something, and it's going to come up.
"I remember coming out after halftime and not being able to see."
And these remembrances, not particularly fond on the Eagles' part, only fuel their desire to go back to Soldier Field and replay that sightless second half -this time sans smoke.
For them, the Fog Bowl was something to build on, to learn from, and to file away as proof that they were quite a team last season. If not for the fog, most of the Eagles passionately believed then, they would have been the team that won the game, they would have marched on to the NFC championship game. They believe it still.
"We lost, but I think we learned something," quarterback Randall Cunningham said. "It was unique. I think we can play with anybody, and we learned that (although) the Bears win the division every year, we're just as good as they are."
It was the Eagles' first trip into playoff land in seven seasons. But once there, they were blindfolded and bound first by their own miscues, then by Mother Nature's whim.
That, they remember.
"I remember just feeling so frustrated, that we waited so long to go to the playoffs, and this happened," Heller said. "It kind of hampered our style. That was in the back of my mind."
Of course, the Eagles blew opportunity after opportunity to pull ahead in the sunny first half. The Bears could not stop the Eagles' offense, but errors, penalties, dropped passes and various other blunders did.
"What I remember most about that game is how many opportunities we had to
put them away, and we didn't," Hopkins said. "How easily we were able to move the ball against them, and the couple of touchdowns we gave them because of busted coverages."
Said Eagles linebacker Al Harris, then a Bears defensive end: "I don't think the fog was a big deal in the game because I thought that Philly had a chance to win it in the first half. If they didn't win it in the first half, I didn't think they were going to win it in the second."
And when the fog came, effectively ending any chance to throw the ball deep, the Eagles hardly could mount a heart-thumping comeback.
In the final totals, they outgained the Bears 430 yards to 341, and Cunningham threw for 407 yards. But the Eagles scored no touchdowns.
When the fog came in, the curtain closed on the 1988 Eagles.
"They were awfully good last year," Bears coach Mike Ditka said of the Eagles this week. "They got to where they wanted to go, and played awfully well until the ominous fog came in.
"Sure, they outplayed us. There's no question about it. They would've won if the fog didn't come in. But these are the little tricks we have in Chicago.
"What do I remember? I just remember that Jackson is a great tight end, and that (running back-receiver Keith) Byars is a great receiver out of the backfield, and the way (Cunningham) threw the ball.
"Thank God the fog did come in."
As usual, Eagles coach Buddy Ryan disagrees with Ditka, at least publicly, saying that "the fog had nothing to do with it."
And Bears middle linebacker Mike Singletary reasonably points out that the fog favored no one.
"The fog came, and we don't practice in the fog, and we don't know any more about it than the Eagles know," Singletary said.
"It's not something that I'm really proud of, to be honest. Whoever wins a game, especially against a good football team, the last thing you want to assume is that you won the game because of the fog. So to me, it's not something that I treasure at all."
But the Eagles, almost to a man, tout a different attitude about the Fog Bowl frolics. They felt they were better then, and they desperately want to show that Monday.
"I thought we were still going to win the game (in the second half), but the fog got so thick," Cunningham said. "We were so confident we were going to win the game that (it was only) when the game was over that we were like, 'Man, they should've called this game off, you know?'
"We didn't think about that while we were out there playing."
While they were, referee Pat Haggerty chose not to halt the game because he said he could stand at the 50-yard line and see both goal posts.
"He probably had the best eyes in the world if he could see that," Hopkins said. "I lost sight of the quarterback when he dropped back. Because you could see about 20 yards. That was about it."
Said Cunningham: "It was very difficult. From where my receivers would line up, I barely could see them. If they ran down the field 15 yards, I could not see them at all."
Now, as the two teams try to peel back the mysteries of that game as they prepare for each other, the fog again obscures mostly everything. By the grace of the technology of game films, the teams have been able to not see the second half all over.
"I watched some of them (Tuesday)," Cunningham said, "and I looked, and Doug (Scovil, the Eagles' quarterback coach) kept running the film, and I'm saying, 'Doug, what are we looking at? I can't see anything.' "
Said Ditka, who tried the same thing: "I was amazed that it was that bad. At least on the sideline I could see the field. I couldn't see the other bench, but I could see the field and I could see the end zone on the north side.
"But when I saw the film, it was a joke. There's nothing to watch. You couldn't see anything."
Films or no films, Monday night will be the time for the Eagles to wash away some of their nine-month-old frustration, and to end their 12-game winless drought in Chicago.
Before the Fog Bowl, Ryan made a big deal of telling everyone that his team was "as good or better" than the Bears at every position except middle linebacker.
"I wanted to be sure last year that (the Bears) knew I felt that my team was as good as their team," Ryan said this week. "And I wanted my team to know I felt they were as good.
"I don't have to worry about that now. My team knows they're as good as the Bears are."
Which might be the lasting legacy of the Fog Bowl. A legacy the Bears want to silence this, in front of another national television audience.
"This week, it's an opportunity to get out there," Singletary said, "and the Lord's will, there won't be any fog."