[1] The series centres on Astrid (Jana Morrison) and Lilly (Samantha Aucoin), two high school outcasts who unexpectedly open a portal to another dimension, and must battle monsters to save the world.

[4][5] "High school is hard enough when you're different, but when outcast BFFs Astrid (Jana Morrison) and Lilly (Samantha Aucoin) accidentally crack open a portal to a terrifyingly quirky monster dimension, it gets a lot more complicated.

"[27] Angie Han of The Hollywood Reporter wrote that Astrid & Lilly has a "charm all its own — not as a copy of what’s come before it, but as a worthy successor", and praised the show's dialogue, humor, and chemistry between the leads.

[1] Bleeding Cool called Astrid & Lilly "a unique and heartfelt story" and praised the show for its "engaging and often hilarious depiction of mixing high school and monster-hunting".

"[1] The show has also been positively compared to a number of acclaimed teen films and TV series including Booksmart, Sex Education, and PEN15.