What Is That Device In Ant-Man And The Wasp: Quantumania's Trailer?

The official trailer for "Ant-Man and The Wasp: Quantumania" is finally here, giving us our first glimpse at the film which will kick start Phase Five of the Marvel Cinematic Universe. The trailer begins by showing us how Scott Lang (Paul Rudd) has been enjoying his reunion with his daughter, Cassie Lang (Kathryn Newton) alongside the fame and success he's earned as one of the Avengers.

For a brief moment, it seems like Scott's life is finally looking up for once — until he is accidentally pulled back into the Quantum Realm, where he comes face-to-face with a host of surreal, otherworldly beings. Front and center, among the mysterious denizens of the Quantum Realm, is Kang the Conqueror (Jonathan Majors) who offers Scott a way out of the bizarre and dreamlike realm he's become trapped in.

Although the trailer makes it clear that most of "Ant-Man and The Wasp: Quantumania" will be devoted to Scott's attempt to escape the Quantum Realm alongside his daughter, one of the most interesting details in the trailer is the reveal of how he actually arrives in the Quantum Realm in the first place — having been sucked into a portal triggered by a malfunctioning device his daughter built.

As of right now, we know very little about what Cassie Lang has been up to since her heartwarming reunion with her father during the events of "Avengers: Endgame" — though the trailer for "Quantumania" seems to imply that she's spent at least some time studying the Quantum Realm itself.

Around 20 seconds into the trailer, we see Cassie presenting a strange device to Scott and several members of the Pym family: Hope Pym (Evangeline Lilly), Hank Pym (Michael Douglas), and Janet Van Dyne (Michelle Pfieffer). This glowing blue device looks similar to the arc reactor which once resided in Tony Stark's (Robert Downey Jr) chest — though this device is bronze-colored and bolted to a small diamond-shaped frame, and the glowing blue light at its core floats up into the air once activated.

Cassie compares her device to a "deep space satellite" for the Quantum Realm, and Janet looks shocked when she realizes that this small machine can send a signal down into the Quantum Realm. Janet's protests against this new technology are too late, as the device appears to malfunction: sending waves of blue energy across the room before pulling Cassie and Scott through a portal into the Quantum Realm.

Although we certainly know that the device's malfunction somehow opened up a portal to the Quantum Realm, it's still unclear exactly why Cassie constructed this strange "Quantum Satellite," as it appears to have absolutely no basis within the comics. In the trailer, Cassie asserts that she built this satellite because "people still need help" — which implies that there are people who need help within the Quantum Realm.

We can only guess who she's referring to here, but considering the fact that Janet spent several decades trapped within the surrealistic depths of the Quantum Realm, it seems very likely that she would know who Cassie is trying to contact. Indeed, her protests about the device all but confirm that she knows exactly who or what is residing within the Quantum Realm — and that contacting them would be a grave mistake.

Later on in the trailer, Janet explains that they have all been transported to "a secret universe beneath ours," and we get several glimpses of a heavily populated area within the Quantum Realm jam-packed with bizarre creatures and people. Cassie's comments could imply that she knows something about the people who reside within the Quantum Realm and that her device was in some way intended to help them — though there's also another possible explanation for why she created this device.

Until the release of "Ant-Man and the Wasp: Quantumania," we can only guess at the true reason why Cassie would have needed to send signals to the Quantum Realm — and although the trailer implies that this device is meant to help people in need, it's also possible that Cassie invented the device in response to Scott's prior disappearance into the Quantum Realm. MCU fans will remember that Scott spent the five years after Thanos's arrival trapped within the Quantum Realm; during which time Cassie believed that he had been snapped away along with 50% of the population.

During all that time, Scott was unable to get into contact with anybody from the outside world, and vice versa. Nobody knew where he was, and nobody could contact him even if they did know. As such, it's entirely possible that Cassie worked on this device as a way to keep in contact with Scott and the Pym family during their exploration of the Quantum Realm — not wanting to lose her father or anybody else on future expeditions.

Indeed, considering the fact that Scott had to become quantumly entangled with Janet in order to communicate with the Quantum Realm in 2018's "Ant-Man and The Wasp," such a device would certainly be very helpful. Unfortunately, there's still no way to know exactly what this mysterious device is for, or why Cassie built it in the first place — though whatever its original intention, it's clear that this device has malfunctioned in a major way.