Langkow scored twice with the extra man while Iginla added a power-play goal and two assists to lead the Calgary Flames to a 4-1 victory. Calgary converted each of its first three man advantages against the league's worst-ranked penalty kill to jump in front 3-0 in the first period.
"Special teams can win you games and tonight was a prime example," said Langkow, who has 24 goals, three shy of his career high. "We come out and get three power-play goals right off the bat and we rolled from there."
Calgary's previous four games - all losses, included a 7-4 drubbing at the hands of Detroit on Sunday that wrapped up a disappointing three-game road trip.
"It was a real tough road trip for us, especially our last game where we didn't show up - period," said Iginla. "As a group of forwards, when we went on the road, we weren't skating enough. Tonight, we were ready."
In those previous four games, Langkow and Iginla had combined for just three assists.
Alex Tanguay also scored for Calgary (30-19-8), which moves them two points ahead of Vancouver and Minnesota into top spot in the Northwest Division.
Denis Hamel, who was claimed off waivers from Ottawa on Saturday, replied for Atlanta (30-21-9). The Thrashers have just one win in seven (1-5-1) and have seen their Southeast Division lead over Tampa Bay fall to just three points.
"We've been just holding on here for the last 15-20 games and we really haven't stepped up and done anything ourselves so maybe this is a wake-up call for us," said Thrashers defenceman Greg de Vries. "We can see them right in our rearview mirror and they have two games on hand on us too. If they win those games, they're ahead of us."
Langkow opened the scoring at 2:59 by nicely deflecting Dion Phaneuf's point shot out of mid-air and past Kari Lehtonen.
At 6:19, Iginla one-timed in a centring pass from Craig Conroy. Langkow made it three goals on four shots at 13:59 when he converted a pass from Kristian Huselius.
"Our penalty killing, there's just no confidence right now," said Thrashers coach Bob Hartley. "We can generate so much good momentum off of our penalty killing but right now it's hurting us big time."
De Vries pointed to the first goal as the epitome of the way things have been going for the Thrashers as of late.
"That first goal tonight was a classic example," said de Vries. "The shot was going wide but they make a great tip and it goes in the far side. You could see the looks on our guys faces, here we go again."
Atlanta has now surrendered 11 power-play goals in its last five games.
Meanwhile, Calgary continues to excel on home ice. The Flames are 9-0-1 in their last 10 and lead the league in wins with a 23-5-1 record.
Hamel got Atlanta on the scoreboard at 10:58 but the Flames answered back just 16 seconds later when Iginla sent in Tanguay down the wing and he fired a quick shot just inside the goal post.
Kiprusoff bounced back with a 21-save performance after getting pulled 13 minutes into Sunday's loss in Detroit having given up three goals on 14 shots.
Lehtonen recovered nicely from his rocky start to finish the night with 23 saves.
The Flames play again on Thursday with a scheduling quirk that sees them play three consecutive games against Colorado - the first two games at home.
Atlanta is off until Saturday, when it plays in Ottawa. They wrap up their season-high six-game road trip in Carolina next Tuesday.
Notes: Calgary D Rhett Warrener returned after missing three games with an arm injury. ... Also back in the lineup for the Flames was RW Tony Amonte after being a healthy scratch Sunday, the first game he had missed all season. Amonte has no goals in his last 14 games ... Flames C Stephane Yelle (foot) did not play and is listed as day-to-day ... de Vries played in his 142nd consecutive game tying him with Slava Kozlov for the longest streak in Thrashers franchise history. ... Calgary has never lost at home to the Thrashers going 4-0.