Invincible season 2 episode 4 ending explained: is Omni-Man [SPOILER] and your biggest questions answered

A teary-eyed Nolan looks at Mark off-screen in Invincible season 2 episode 4
Invincible season 2's mid-season finale is full of explosive moments. (Image credit: Prime Video)

Invincible season 2 is over – for now. With this season's fourth episode released, the popular Prime Video series is leaving our screens as it embarks on a mid-season break.

But fret not, Invincible fans, because season 2 will return for its second installment in early 2024. In October, co-showrunner Simon Racioppa exclusively told us it "wasn't the original plan" to split the season in two, but there we go.

Seeing one of the best Prime Video shows go on hiatus is all the more frustrating considering how the season 2 mid-season finale – titled 'It's Been a While' – ended. Luckily for you, we're here to deliver some much-needed answers to your biggest questions. Before the series returned on November 3, we sat down with Racioppa and Invincible's comics co-creator Robert Kirkman to get the lowdown on season 2 episode 4's suspense-filled ending, what its post-credits scene means, and more.

Full spoilers follow for Invincible season 2's mid-season finale. Turn back now if you've yet to watch it, or read our Invincible season 2 part 1 review if you haven't even started season 2.

Invincible season 2 episode 4 ending explained: why is the hit series taking a break?

Nolan and Mark look at their Viltrum enemies, who stand off-screen, in Invincible season 2 episode 4

"Look, Mark! Why do you think we're taking a mid-season break?!" (Image credit: Prime Video)

Before we dig into the mid-season finale – feel free to skip ahead – one of the biggest non-spoiler-based questions fans have is why is Invincible season 2 taking a short break?

"We're still putting the final polish on the last four episodes," Kirkman told TechRadar in late October. "So it made sense, scheduling-wise, to take a break over the holidays. We also realized that there's a really strong narrative break [between episodes 4 and 5] that makes season 2 feel like two completely different seasons, and it gives us a lot of opportunity to build anticipation for episode 5."

Invincible season 2 episode 4 ending explained: is Omni-Man paralyzed?

An injured Mark looks over at his paralyzed father Nolan in Invincible season 2 episode 4

Don't worry, Nolan will be fine, we think... (Image credit: Prime Video)

Yes, but not permanently. Viltrumite physiology means faster recovery from even the most life-threatening wounds. Just look at how quickly Mark recovered after Nolan nearly beat him to death in Invincible's season 1 finale – it only took two weeks for Mark's physical wounds to heal. 

You can expect Nolan to make a full recovery. However, considering Lucan broke Nolan's back during the surprise attack in episode 4's final moments, Nolan will need more time to fully heal, so fans shouldn't bank on seeing him back in action any time soon. 

Well, unless the Viltrum Empire's presumably advanced medical technology aids his recovery. Given that Nolan is set to be executed for abandoning his post on Earth, having another son (more on this shortly), and betraying his own race, though, we can't see his fellow Viltrumites helping him.

Invincible season 2 episode 4 ending explained: who is General Kregg? And what does he warn Mark about?

General Kregg looks down at an off-camera Mark in Invincible season 2 episode 4

Another of Invincible's big bads has finally arrived. (Image credit: Prime Video)

General Kregg is the current leader of the Viltrum Empire's army. Little is known about his origins in the source material, so there's not much to fill in non-comic readers on here. He is thought to be thousands of years old, was one of the survivors of Viltrum's Great Purge event (alongside Nolan), and has risen through the ranks to command his planet's armed forces.

Kregg only makes a brief appearance in season 2's mid-season finale, but it's nonetheless a cold-hearted cameo. He initially pays Mark a back-handed compliment for proving he's worthy of his Viltrumite heritage – you know, considering Mark goes toe-to-toe with Viltrumite warrior Thula. However, his mood changes quickly as he presents an ultimatum to Mark: return to Earth, assume his father's role, and convince humanity to surrender to Viltrum. If Earth stands against Viltrum upon the tyrannical race's arrival, they'll conquer the planet by force, killing millions in the process.

Viewers should expect to see more of Kregg and Lucan, plus more of Viltrum, in the seasons ahead. While he couldn't confirm how much you'll see of Invincible's main villains in season 2 part 2, Racioppa hinted there's much more story to tell about these characters as their roles become more prominent in its overarching narrative.

"You're going to see elements," Racioppa said. "We're just sowing the seeds for stuff that's going to pay off multiple seasons down the line, so we've only given you a taste of the Viltrum Empire and the interstellar politics at play. We're laying the groundwork and introducing audiences to Invincible's expanded universe, getting off planet Earth for a bit, and seeing the major players out there."

Invincible season 2 episode 4 ending explained: what are the books Omni-Man tells Mark to read?

A screenshot of Nolan Grayson's books in Invincible season 2 episode 4

What will Mark learn about his father from the latter's books? (Image credit: Prime Video)

Considering viewers had to wait until episode 3's final moments to be reunited with Nolan – a scene Racioppa told TechRadar was almost held back until the mid-season point – it's disappointing that we might not see him for a while again.

However, audiences will learn more about his past in season 2 part 2. Before a paralyzed and incarcerated Nolan is carted off by the Viltrum Empire, he tells a severely injured Mark to "read my books". 

Long-time fans will know the significance of this tease, but casual observers may not fully grasp what it means. Towards the end of episode 4, Debbie finds – and later discards in a box on the roadside – a series of novels that Nolan penned. Is this the same literature Nolan tells Mark to seek out and study? If so, will Mark return to Earth in time to locate them before they go AWOL? And, most importantly, what will Mark learn if he reads them?

"The biggest moment there is not what the books represent and what they'll lead to, but the fact that Nolan is actively steering Mark to them and why that is," Kirkman teased. "What is that change in Nolan's character that's led to this moment? Why is he doing that? I think that's somewhat clear to viewers, but I'll refrain from suggesting anything else."

Invincible season 2 episode 4 ending explained: who is Oliver Grayson?

A screenshot of Nolan holding Oliver while Andressa stands next to him in Invincible season 2 episode 4

Well, this is another big surprise Nolan has in store for Mark (and for us)... (Image credit: Prime Video)

Oliver Grayson is the son of Nolan and Andressa, one of Thraxa's bug-like aliens who married Nolan after a) he saved some Thraxans from crashing into a black hole, b) he became the Thraxans' emperor, and c) she fell in love with him. This means he's also Mark's half-brother.

Given who Oliver's parents are, he's a Viltrum-Thraxan hybrid. He has the anatomy and physiology of a Viltrumite, which means he ages more slowly than Thraxans (they only live for a year), but his skin is purple, owing to his part-Thraxan genealogy.

Unfortunately, Oliver's skin color immediately paints a target on his back. As Nolan reveals, Viltrumites are only supposed to breed with genetically similar species, such as Earth's human populace. If Viltrum finds out about Oliver (which they do), they won't hesitate to kill him due to his supposed impurity. That's why Nolan asks an extremely reluctant Mark to help him keep Oliver safe when Lucas, Thula, and Vidor arrive.

Diehard fans will know how this newfound responsibility affects Mark's story, but what can Kirkman tease – for unaware viewers – about Oliver and his impact on Mark? Will Mark return to Earth with Oliver in tow, train him just like Nolan did with Mark, and ask for Oliver's help in defending the planet from the Viltrumites? What will Debbie make of Nolan cheating on her after the trauma she's already suffered? And will she be able to love Oliver like her own son?

"We're trying to show Mark as a very capable, thinking, able-to-handle-anything superhero," Kirkman said. "And Oliver becomes another important part of that storyline. Mark gets his father back, but it comes with even more complications and pressures that are going to weigh him down.

"The story of Invincible is really about this poor, downtrodden character called Mark Grayson who gets every possible thing thrown at him every possible time, but he rises to the occasion at every opportunity. So the Oliver storyline will continue to show just how strong Mark is as a character."

Invincible season 2 episode 4 ending explained: where's Angstrom Levy?

Angstrom Levy stands in front of some multiversal portals in Invincible season 2

Wait, where is Angstrom in all of this? (Image credit: Prime Video)

One of season 2's biggest mysteries surrounds Angstrom Levy. He was a major player in this season's first episode, with Invincible season 2 episode 1's post-credits scene setting him up as one of Mark's chief nemeses. 

However, after a brief appearance in season 2 episode 2's mid-credits stinger, Angstrom hasn't been seen since. So, what gives? Why has Angstrom been absent for the past two episodes? And what can audiences expect upon his return?

"We've tried to stick closely to the books where Angstrom is concerned," Racioppa teased. "If you've read the comics and you've seen his arc in them, you can be sure we're doing a version of that. Whether it'll be beat for beat or changed a little bit to expand or contract things, you'll have to wait to find out. But you'll definitely see more Angstrom." 

Invincible season 2 episode 4 ending explained: is Donald Ferguson a robot?

A close up of a stunned Donald in Invincible season 2 episode 4

Season 2 episode 4 reveals more details about how Donald is alive. (Image credit: Prime Video)

Another curious plot thread involves Donald Ferguson. Cecil Stedman's right-hand man died in season 1 episode 7, with the Global Defence Agency (GDA) employee sacrificing himself to try to kill Omni-Man as the latter sought revenge on the GDA for uncovering his crimes.

Viewers, then, were as stunned as Debbie Grayson was to see Donald alive and well in season 2 episode 3. Unsettled by Debbie's shocked expression, Donald turns up at the Grayson home seeking answers. When he realizes nobody's home, he heads across the street to examine the remains of a destroyed house – actually a GDA surveillance site to keep tabs on Omni-Man – that seems familiar to him. There, Donald finds a pair of broken glasses – the same make as his own spectacles – which perplexes him.

Returning to the GDA's headquarters, he reviews the security camera footage from the wrecked home and learns the truth: he was killed by Omni-Man, and he did sacrifice himself to try to stop the rampaging Viltrumite.

Distressed, Donald finds a vacant GDA restroom to make sure he's a) actually human and b) is still alive. Over the restroom's sink, he cuts his arm with a switchblade, and, to his relief, blood pours out. However, seconds later, Donald realizes the blade's knife edge has been bent out of shape. What the heck is going on?

Unfortunately, we don't get an answer before the mid-season finale ends, but we have a theory. We think Donald is a robot – more specifically, an advanced version of the ReAnimen, aka the mechanical humanoid zombie creatures created by scientist D.A. Sinclair in Invincible season 1. In the final episode of the show's first season, we see Cecil has employed Sinclair to make an army of ReAnimen, which the GDA will potentially use to fight the Viltrum Empire when it inevitably invades Earth.

It's possible, though, that Cecil also asked Sinclair to make a more intelligent version of his ReAnimen to bring Donald back to life. It's that, or Donald is a cyborg and has been one his entire life. We'll find out for sure when season 2 part 2 arrives early next year.

Invincible season 2 episode 4 ending explained: is there a post-credits scene?

Mauler Prime drinks some lemonade made by his clone in Invincible season 2 episode 4

Thursday might be chicken pot pie day, but Friday is 'kill-your-clone with lemonade' day. (Image credit: Prime Video)

Yes, there is – although it's not a scene that holds any major significance, nor does it greatly advance the series' overarching narrative.

In it, we see the so-called Mauler Prime putting his clone to work on building a new clone-creating machine so Mauler Prime can make an army of genetically identical duplicates to do his bidding. Oh, and he wants to be known as King Mauler from now on, so there's no question about who's in charge.

Unfortunately for Mauler Prime, he's not long for this world. After drinking a glass of lemonade from his clone, Mauler Prime suddenly feels unwell. It turns out his clone laced the drink with micro toxins, which kill Mauler Prime and result in his clone becoming Mauler Prime 2.0. 

If nothing else, it's another amusing addition to the series' long-running joke about who the original Mauler twin is (or, rather, was). Expect this gag to run and run and run...

For more Prime Video-based coverage, read our guides on all of the new Prime Video movies, the best Prime Video movies, and how much a Prime Video subscription costs.

Senior Entertainment Reporter

As TechRadar's senior entertainment reporter, Tom covers all of the latest movies, TV shows, and streaming service news that you need to know about. You'll regularly find him writing about the Marvel Cinematic Universe, Star Wars, Netflix, Prime Video, Disney Plus, and many other topics of interest.

An NCTJ-accredited journalist, Tom also writes reviews, analytical articles, opinion pieces, and interview-led features on the biggest franchises, actors, directors and other industry leaders. You may see his quotes pop up in the odd official Marvel Studios video, too, such as this Moon Knight TV spot.

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