After watching the heart-pumping premiere of "Teen Wolf," we decided to kick off a recurring feature called Asthma Alert. Every week, we'll sift through the nail-biting moments and highlight key scenes that literally took our breath away. Grab your inhaler and let's talk about Episode 4!

1. Kate Gets Attacked By The Alpha Wolf

The episode opens with an unidentified woman (later we learn that she's Allison's aunt) driving down a dark road. She appears quite nervous, but we've got no clue what's about to happen until a terrifying red-eyed beast sprints up alongside her.

2. Scott Goes Digging Through Kate's Things In Search Of The Bullet

Derek's life was hanging by a thread, so Scott agreed to look for the bullet that wounded his arm. While having dinner at Allison's house, he went rummaging through her aunt's bags and found what he needed in just the nick of time.

3. Derek Asks Stiles To Saw His Arm Off

Stiles was put in a terrible position when Scott dumped Derek in his hands. Fearful that the poison from the bullet would reach his heart and kill him, Derek insisted that Stiles saw his infected arm off immediately. He was about to do it, too, but luckily Scott finally arrived.

4. Scott Meets Peter Hale

Derek took the wide-eyed Scott to Beacons Crossing Home to meet his uncle, whose face was deformed after the Argent family set fire to Derek's house. Just as D finished his sad story, he spun his relative around to reveal his burned skin.

+ What was your favorite nerve-racking moment of the night? Sound off in the comments and let us know what got your adrenaline pumping!