...and they're pretty good episodes. They haven't aired yet in the states.
The episodes were
1. Nightmare In Red - The Avengers fight the Red Hulk. Apparently someone (I thought it looked like senator kelly but it turned out to be Dell Rusk) set it all up but Winter Soldier stole a blood sample of the Hulk's from SHIELD's heli-carrier and gave it to General Ross and the blood turns him into the Red Hulk. Falcon who is also on the mastermind's payroll attacks Bruce and Hawkeye and blocks Bruce's power with some type of adrenaline inhibitor. The Hulk is wrongly blamed for Rulk's rampage onboard the heli-carrier and is convinced to turn himself into SHIELD by Skrull Cap who did so to get Hulk out of the way for the invasion.
My favorite part of the episode was Bruce and Hawkeye going fishing. Apparently Bruce and the Hulk have worked out an arrangement where Bruce allows Hulk to stay in control for every day of the month but one so he can serve in the Avengers. Bruce chose to spend his day doing something relaxing like fishing. I thought that was just a cool character moment there.
2. Prisoner Of War - The real Captain America leads a group of Skrull prisoners (including Viper, Clay Quartermain, Sue Storm, Gyrich, Mockingbird and a top level AIM dude in line to become the next scientist supreme) into escaping from a Skrull ship that's parked near Saturn I believe. The Skrulls try to torture Cap but eventually give up on that tactic as he won't break. Later they try to trick him into thinking he was being rescued by the Avengers but he's not stupid enough to fall for the trick. He joins up with the other prisoners and the episode ends with them making their way back to earth. Viper saves Cap in the episode but she swears they will be enemies once the Skrulls are defeated. Oh yeah the prisoners have to fight Super Skrull to get off the ship. And there is a brief flashback cameo of Galactus decimating the Skrull homeworld (that's why they want earth...they want a new homeworld...and a prophecy told them earth should be there new home)
3. Infiltration - The Skrulls kick off their plan by activating their saboteur spies in AIM, SHIELD, SWORD, the Fantastic Four. Dr. Doom (or is it a skrull pretending to be him) appears to Iron Man and claims to offer a way to stop the Skrulls. He chides Iron Man for the Avengers messing with his plans earlier in the season because he was working on a way to detect the Skrulls. He offers Tony a device that he has to integrate into his armor that will supposedly allow him to see through the Skrulls disguises. Tony asks Doom to help them fight the Skrulls and Doom more or less says that sort of thing is beneath him and that's what lower people like Tony and the other heroes are for and he flies off. The Skrulls have seriously compromised SHIELD and it's shown almost everyone there but Maria Hill is one. They try to get her to surrender and offer her a great new job as a liasion amongst them and their new human slaves but she turns them down so they try to kill her only to find out this Maria was an LMD. Nick Fury and some female SHIELD agent I'm not sure I'm supposed to recognize or not have put the clues together that Cap is a Skrull by looking at news footage of the battle between the Avengers and the Kree a while back and another case which slips my mind at the moment. Mockingbird/Vernake attacks Nick and Iron Man shows up and it turns out she's gotten a virus into Tony's armor (I didn't entirely understand this...I assume the very much in character Doom who helped Tony was a Skrull and the thing Tony integrated into his armor uploaded the virus but I don't remember Vernake doing the super villain thing and bragging about Tony falling for her deception...I'm 80% sure Tony got the virus from Doom but a part of me wonders if he was infected another way because that Doom Tony scene was so good and I don't remember anything explicitly saying Doom was an imposter).
Ms. Marvel shows up in Wakanda after chasing a Skrull ship and encounters the Avengers including the Black Panther and someone claiming to be T'Challa arrives with his body guard and security systems. Ms. Marvel can't tell if the T'Challa who is leading the Wakandans is a Skrull of if this group of Avengers is the Skrulls (it's the Avengers). The real Hawkeye and Wasp show up and the Skrulls are defeated. One thing I got confused with this episode was the Skrulls reaction to Ms. Marvel. Jan Skrull mentioned something about Ms. Marvel's costume that she got a few episodes back like she had never seen it before. I couldn't tell if A)The Skrulls intelligence was sloppy or B) I was wrong and the real Jan had never seen that costume before either so the Skrull intelligence was accurate or C) there was a continuity error. I was sure the real Avengers and Jan had seen Carol in that red costume before but if Skrull Jan was wrong about that it should have been a red flag to Carol who is already suspicious that they could be Skrulls...it seemed like Carol was a little suspicious of the question...but to me it should have been either a red flag or not suspicious in the slightest rather than somewhere in between the two. Or maybe I'm making a mountain of a continuity detail that I shouldn't.
4. Secret Invasion - Vernake and her super skrulls have a showdown with
the Avengers. I loved how Skrull Cap was used here. Vernake uses Skrull Cap to convince the people of earth that the Skrulls come in peace and are here to stop disease and war. She uses his reputation as her ultimate weapon to help enslave earth. The Avengers have show down with Vernake and the Skrulls in Washington DC. I just went to Washington DC for the first time a month ago so it was neat to see super hero battles at a bunch of monuments I just visited a month ago. One thing that I thought was amusing is that the battle makes it look like the washington memorial is in the front yard of the capitol building (like one skrull wraps around the washington monument and throws one of the heros into the front yard of the capitol building like it's just right there instead of a mile of the National Mall in between the two). Anyways Thor shows up and they defeat the scummy Skrulls. Unfortunately the Skrulls have also damaged the heroes reputations and Thor remarks that it is going to take longer to repair that than the building and broken bones. As the episode ends you can clearly see Cap has been hurt by the hit to their reputation. The Skrulls took from him the one thing he thought no one could take away from him...his good name.
5. Along Came A Spider - The Avengers are dealing with the aftermath of their reputation being besmirched by the Skrulls. Tony goes to J Jonah Jameson to demand a retraction after a news story slanders Cap's role in the Secret Invasion and I liked the mention that the Avengers, FF, SHIELD and even the President have vouched for Cap's innocence and Jonah isn't buying it. Jonah makes a deal that if Tony can get the Bugle an interview with Cap he'll see what he can do. Jonah assigns Betty as reporter on the case and a 17 year old Peter Parker as photographer (not sure if this is supposed to be the same spider-man in the current ultimate spider-man show or not). Clay and SHIELD agents are transporting Viper when their vehicle is attacked by the Serpent Society. Cap and Spider-Man show up and Cap, Spider-Man and a group of civilians end up stuck down below in the sewer system trying to find another way out. Cap is having a hard time because no one trusts him after the Skrull incident. There is a particularly awesome character moment when Spider-Man talks to Cap in private and asks Cap how he can stand the bad publicity and the lack of respect everyone is giving him and Cap remarks that it's no different than what Spider-Man himself goes through all the time and that just like Spider-Man he doesn't do it for the glory. Spider-Man is pretty moved and jokes that he wants to be Cap's sidekick. I thought this was a really good moment not because it shows what makes Steve tick but because it shows that Steve knew what makes Spider-Man tick...he knows the Bugle is wrong about him and that there really are people in the marvel universe who aren't stupid enough to believe the Bugle. Anyways the Serpent Society and Viper attack again and have couple nifty fight scenes and eventually the civilians take up for Cap and Spidey and start throwing rocks at the serpent society and spidey saves them all from the sewer collapsing on them until the Avengers find them and save him from being crushed.
6. Behold...The Vision - The Vision is sent by some mastermind (Ultron) to retrieve adamantium, vibranium and Cap's SHIELD. Cap, Hawkeye and Thor go to Wakanda to meet up with T'Challa who says his peoples technology can repair Cap's broken shield. T'Challa does not want to rejoin the Avengers and a comment is made by T'Challa about how Tony more or less quit on the team due to the Skrull mischief (Tony came back in an earlier episode but I guess T'Challa wasn't around for that). Anyways first the Vision attacks Avengers mansion where Wasp and Jane Foster are watching movies and smacks them around a bit and brings the room crashing down by phasing and pulling out one of it's support beams or something. I think he needed Adamantium which was at the mansion. Later he goes to Wakanda to get Cap's shield and fights the Avengers. He really beats the crap out of them(which is odd considering in comics somebody usually takes him out pretty quickly so he can't do any damage...this shows what he can do when he really has the upper hand). He even shrugs off Thor hitting him with his hammer. He also tries to steal vibranium from the vibranium mound (I liked T'Challa's acknowledgement that if a villain shows up in Wakanda...it almost certainly revolves around stealing vibranium). Eventually Black Panther reconstitutes Steve's shield while Vision is trying to steal it and once Steve gets the shield back all of a sudden the tide turns and they start putting the hurt on Vision. We found out at the end of the episode Ultron wanted the adamantium and vibranium for his new body.
One thing I thought was funny was Hawkeye's rudeness to T'Challa. Apparently he's pretty peeved T'Challa doesn't want to rejoin the Avengers after the Skrull stuff and Tony's rude way of calling it quits. Clint makes a comment earlier in the episode that according to T'Challa's peoples traditions he has a right to challenge T'Challa for the throne. Later in the episode after the battle with the vision is over he makes a move on T'Challa and T'Challa puts him in an arm bar or something and Hawkeye says something like "fine you can keep your kingdom T'Challa". I can't remember the exact line but it was funny.
Not sure why you were confused about the reference to Ms Marvel's costume. The statement was consistant with the Skrull Avengers stating they were abducted at the end of season 1 after returning from Asgard, before Ms. Marvel emerged in her new costume.
I agree with you that the episodes are great, and it was better than the flop Secret Invasion was in the comics.
What I liked about this second Season is how they have portrayed the power levels of Ms Marvel and Vision so far. Both are powerhouses they should be but often aren't in the comics.
I find they also hit a lot of right notes with other characters, making them all unique and with flaws and strengths.