'The Last of Us' star Lamar Johnson says his character Henry 'would not have been able to stomach' a world without his brother Sam

• Lamar Johnson spoke about "The Last of Us" episode 5 in an interview with Entertainment Tonight.
• Johnson, 28, said his character Henry "instantly regrets" what he did to his brother, Sam.

"The Last of Us" star Lamar Johnson offered insights into his character Henry's thoughts following the gut-wrenching twists in episode five.

The latest episode of the HBO Max series introduces audiences to Henry (Johnson), and his younger brother Sam (Keivonn Montreal Woodard), who ambushed Ellie (Bella Ramsey) and Joel (Pedro Pascal) in the previous episode.

After becoming acquainted, the four decide to travel to Wyoming together. However, the plan stalls when Sam becomes infected and attacks Ellie – who's immune to the infection – in the middle of the night. The event leads to Henry shooting Sam, then fatally shooting himself.

"It was a split decision and I had to shoot him," Johnson, 28, told Entertainment Tonight's "The Last of Us" podcast, "The Last of Pods," published Saturday.

"But as soon as Henry shoots Sam, there's a wash of emotions that go over him. But I think, ultimately, if I was gonna say one word, just, shock. He's shocked. As soon as he shoots him, he instantly regrets it and is in shock. He even asks, 'What did I do?' He's just in shock."

Some fans, including Ginx Esport TV's Ashleigh Klein, noted on Twitter that the series changed Henry's dialogue in the scene, with him asking, "What did I do" instead of placing blame on Joel.

Johnson then reflected on his character's decision to take his own life.

"I like to believe that Henry is a God-fearing man and he saw that Sam had passed and he wanted to join his brother," Johnson told the outlet.

Johnson added that "Sam is Henry's will to live" and "he is his purpose."

"He would not be able to stomach living in this world, as harsh it is as it is, without Sam – especially after all of his efforts, after all that they've both been through: losing both their parents and just having one another," Johnson told ET. "It was just a tough thing for Henry to have to stomach. He definitely would've been very depressed. It would've been on his mind. It would've eaten him away, would've eaten him alive."

Fans of "The Last of Us" are likely still reeling from the emotional events of episode four, which starred Nick Offerman and Murray Bartlett. Insider's Kirsten Acuna reported that the series expanded on the source material by giving a poignant glimpse into the pair's romantic relationship as opposed to the video game, which only implied a relationship.

Unlike episode five, which aired two days early on Friday due to Super Bowl LVII, episode six will premiere on February 19 on HBO Max.