PremXL is about how Mihir falls in love with Diya, a new admission to Happy Girls' PG, a girls' hostel run by his mother. Mihir and Biki are childhood friends and partners in crime, while Diya has her PG mates Dhriti and Gauri. In a twist of events, all of them become good friends, as Mihir's one-sided love for Diya grows. It's a romantic take on a slice of life.