The following contains spoilers for Secret Invasion, now streaming on Disney+.
The Marvel Cinematic Universe introduced the Skrull race in Captain Marvel, a movie set in the '90s. However, the Skrulls weren't seen again until after Thanos attacked. As a result, much time and growth took place so that certain characters could evolve off-screen. Now, Secret Invasion has reintroduced the Skrulls as a race still struggling to find a place in the galaxy. However, rather than working together to find a home, hundreds have splintered off in hopes of rising again, this time by force.
Since Skrulls don't have the means to enact a full-scale invasion, they've resorted to using deceptive tactics, taking the faces of those they kidnap and their memories. This has made them almost undetectable to the average person but also showed a major advancement in one of their abilities. In the past, Skrulls could only take recent memories of those they copied, but now, they could take their entire lives without a struggle.
How Skrulls Took Memories in Captain Marvel
When Carol Danvers was taken by the Skrulls, their advanced tech was unlike anything seen before. For starters, they had a machine that allowed them to peer into the minds of a subject and see their memories from as far back as childhood. This was similar to their ability to steal memories from those they copied but far more advanced. Even Talos explained that when they assumed the identity of another, they could only take recent memories of their host, likely because of the strain it would put on their mind.
While this made sense at the time, decades have shown that the Skrulls have grown stronger in their ability to take memories and, in Gravik's army, have used their power to lead terror attacks. For now, it's not explained how the Skrulls enhanced this ability, but considering they took memories once the subject was placed in a stasis machine, it could have something to do with the machine. However, it could also be that Gravik and a select few taught themselves to push their minds and imparted this ability to others, making them the perfect moles.
The Skrull's Advanced Abilities Make Them Deadlier Threats
Captain Marvel showed the potential the Skrulls had as enemies who could infiltrate and use superhuman strength to defend themselves. However, the movie never properly explained the tactical prowess they could use and the devastation they could inflict. Secret Invasion, in its first episode alone, has shown that Skrulls were always a major threat that was never properly monitored. Now, with their ability to take the memories of a host's entire life, nothing could stop them from infiltrating and taking over the highest positions.
Unlike past enemies Nick Fury has faced, the Skrulls were allies that turned on those that didn't agree with them and evolved. Now, they're the deadliest force the MCU has seen since Thanos and have already started to destabilize the already shaky peace that existed in the world. If left unchecked, it wouldn't take long for the Skrull Empire to take over the world, and a large percentage of that is due to the memory-stealing ability they grew over time.
Secret Invasion releases new episodes every Wednesday on Disney+.