Flyers backup goalie Ray Emery, who went 17-1 and won a Stanley Cup ring with the Blackhawks last season, did not make a stirring return to Chicago. Emery allowed four goals on the first 10 shots he faced.
Emery, who was pulled early in the third period, had little help in front of him as the Flyers finished their 13-day road trip with a 2-3-1 record.
"As a whole, I have to play better," Emery said.
Chicago scored five second-period goals - the first three in a 4-minute, 44-second span early in the period to wipe out a 1-0 deficit - and embarrassed the Flyers, sending them to their third straight defeat.
Duncan Keith (power play), Andrew Shaw, and Michal Handzus scored goals early in the second period to ignite Chicago. Handzus, a former Flyer who netted a shorthanded goal after Jake Voracek lost the puck in his end, scored on a two-on-one in which he appeared to kick the puck into the net.
The Flyers got to within 3-2 on Steve Downie's power-play goal, but Kris Versteeg, another former Flyer, made it 4-2 after taking a nice behind-the-net feed from Brandon Saad midway through the middle period.
Patrick Sharp - yep, another former Flyer - increased the lead to 5-2 when his shot deflected off teammate Jonathan Toews' arm and into the net with 5:45 left in the second period. Toews got credit for his 13th goal. The three former Flyers combined for seven points.
Just 1:05 into the final period, defenseman Brent Seabrook scored when his stick snapped and his knuckleball shot got past Emery (six goals on 18 shots), ending his night. Steve Mason entered.
"This is a good test for us; these guys are tops in the league, especially at home, and they play a really fast hockey game," Timonen said before the opening faceoff. "I'm looking forward to it, actually, to see where we match up against these guys. We've got to be ready."
They were, playing their most impressive opening period of the road trip, building a 1-0 lead on Voracek's power-play goal, outshooting the hosts, 10-6, and outhitting them, 15-5.
Chicago, playing its second game in as many nights, found its legs in the second period and put on an offensive clinic.
"We started the game well and then took a few shifts off, and against a team like this they're going to make you pay," defenseman Nick Grossmann said.
The Flyers had lost their previous two games on the trip, falling to Dallas, 5-1, and dropping a 5-4 shootout in Ottawa.
"A couple games kind of got away from us," winger Matt Read said. "We haven't been playing our best hockey. . . . It's been a long road trip and I'm excited to get home."
There's no rest for the weary. On Thursday, the Flyers host Danny Briere and Montreal.