It follows alternate versions of the character who escape from the mysterious Time Variance Authority (TVA) but get stranded in an apocalyptic event and must work together to survive.

Tom Hiddleston reprises his role as Loki from the film series, while Sophia Di Martino stars as a female version of the character named Sylvie.

[3] Herron and head writer Michael Waldron executive produce alongside Hiddleston and Marvel Studios' Kevin Feige, Louis D'Esposito, Victoria Alonso, and Stephen Broussard.

[13] The episode stars Tom Hiddleston as Loki, Sophia Di Martino as Sylvie, Gugu Mbatha-Raw as Ravonna Renslayer, and Sasha Lane as Hunter C-20.

[10][14]: 37:36–37:53  Also appearing in the episode are Susan Gallagher as a Lamentian homesteader, Alex Van as Patrice, Ben Vandermey as Private Hudson, and Jon Collin Barclay as Corporal Hicks.

[8] Herron decided to feature a single-take for that sequence in order for the audience to feel like they were with the characters in that moment, as well as to heighten the horror and terror of the apocalypse.

[24] Early discussions had considered including a motorcycle for Loki and Sylvie to get on and off, but Arkapaw said it made the sequence too "complex" and took away from the "humanistic" feel.

[25] Visual effects for the episode were created by Digital Domain, Lola, FuseFX, Rodeo FX, Method Studios, Luma Pictures, Cantina Creative, Crafty Apes, and Rise.

[27] Marvel approached Norwegian author Erlend O. Nødtvedt and musician Benedicte Maurseth to create the Asgardian drinking song sung by Loki in the episode.

[28][29] Hannah Shaw-Williams of Screen Rant thought while the chorus was "cheerful and upbeat", the verse heard in the episode was "far more melancholy" with poignant lyrics that "captures Loki's self-imposed isolation and loneliness".

Holt then suggested to Herron and co-executive producer Kevin Wright that the moment should have music coming from train passengers with instruments, arranging the track first on violin before sending it to the Norwegian musicians who worked on the score.

[35] Nielsen Media Research, who measure the number of minutes watched by United States audiences on television sets, listed Loki as the most-watched original streaming series for the week of June 21 to 27, 2021.

The site's critical consensus reads, "The charming Sophia Di Martino proves a worthy variant in "Lamentis," an apocalyptic pit stop that wears its Whovian influences on its tricky sleeves—for better and worse.

"[37] Reviewing "Lamentis" for Rolling Stone, Alan Sepinwall said a series consisting of six episodes like this should not have time to veer away from its main narrative to further explore the characters.

Sepinwall also believed the episode was "an excellent example of the ways in which these new MCU shows can do things differently from the films while still feeling like part of the same broader story".

[38] Siddhant Adlakha at IGN said the episode "hammers home just how much this series is the rare Marvel entry with any real visual panache.

He also felt Loki should "let loose" and "luxuriate in the infinite chaos just outside its frame", wishing "Marvel's production machine [would] get out of [the creative's] way and let them tell an immersive story, where the characters aren't defined by a visual and narrative formula, but by possibility"; Adlakha gave "Lamentis" a 7 out of 10.

[40] Yahoo Entertainment's Ethan Alter believed Sylvie would ultimately be a fusion of Lady Loki and Enchantress, which had been a prevalent fan theory.

Club called the reveal "a major deal for MCU fans" but did not find it surprising, since Loki in the comics is pansexual and gender fluid.

She said that, in addition to Phastos being gay in Eternals (2021) and Valkyrie's bisexuality being explored in Thor: Love and Thunder (2022), Marvel Studios was "clearly trying to overcome the flak for being late to the party with its dismal LGBTQ+ representation".

[17] Doctor Who writer Russell T Davies, however, criticized the scene which reveals Loki as bisexual as a "feeble gesture towards the vital politics and the stories that should be told".

However, Vary was discouraged that the acknowledgment was being celebrated as a milestone for queer representation since other superhero media had already embraced that community such as with multiple characters in DC Comics television series including the Arrowverse.

Vary concluded that it was a "significant step forward for LGBTQIA representation" in the MCU, but it remained to be seen if Loki would be able to "express same-sex love or sexual attraction" like heterosexual couples have done in the franchise.

[11] At the 2022 Visual Effects Society Awards, Jesse Lewis-Evans, Luke Avery, Autumn Durald Arkapaw, and Scott Inkster were nominated for Outstanding Virtual Cinematography in a CG Project for the "Race to the Ark" sequence, and Paul Chapman, Tom Truscott, Biagio Figliuzzi, and Attila Szalma were nominated for Outstanding Compositing and Lighting in an Episode for the "Shuroo City Destruction" sequence.