Mad Sweeney (Pablo Schreiber) was killed off in the finale of American Gods season 2, but Liam Doyle (Iwan Rheon) could very well be Mad Sweeney reincarnated. Fan-favorite Mad Sweeney, arguably American Gods' best character, was an integral part of the first two seasons, a hapless leprechaun whose luck ran out after accidentally giving his lucky coin away to Shadow Moon (Ricky Whittle) who then passed it onto his resurrected wife, Laura Moon (Emily Browning). In one of the series' best episodes to date, season 2's "Treasure of the Sun," it's revealed the unlucky leprechaun was once the noble King Lugh of the ancient, magical Tuatha Dé Danann race of fae folk.
The foul-mouthed, short-tempered Mad Sweeney's true noble nature peeked through, particularly when it came to Laura, with whom he'd quietly, reluctantly fallen in love. Mad as he was, Mad Sweeney still operated by the rusty vestiges of his old code of honor, even if he couldn't quite remember his past. Part of that involved him never just taking his coin back from Laura Moon, even though it would have meant restoring his luck; the coin was the only thing keeping her alive and he refused to let her die even at great expense to himself. It's this very coin that hints that there may be more to Doyle than meets the eye.
Liam Doyle first made his appearance in season 3 as a leprechaun who had lost his lucky coin and who now spent his days as a humble bartender. On the surface, he's as different from Mad Sweeney as one can possibly be. He's charming where Sweeney is abrasive, reluctant to engage in violence where Sweeney was always aggressive, and looking for redemption where Sweeney was just trying to survive. But digging deeper, there are a number of similarities that hint he may actually be Mad Sweeney reincarnated.
He's clearly drawn to Laura, continuing to stick with her even after he breaks into Mad Sweeney's hoard to retrieve the spear Gungnir for her and his part is done. The most telling thing, however, is when Laura confronts Wednesday with Gungnir: Doyle tosses the lucky coin to Laura in order to help her aim be true even as a killing blow from Czernobog (Peter Stormare) bears down on him in a decision eerily reminiscent of Mad Sweeney. A leprechaun's lucky coin is the thing most dear to them in the world, especially if they've already lost it once. For Doyle to willingly give his coin up to Laura and potentially sacrifice himself meant he must have some powerful feelings for her, indeed - feelings no other character aside from Sweeney had really shown.
It's entirely possible that Doyle is just driven by the need to redeem himself for the sins of his past and that's the root of his desire to help. Even so, his interest in and connection to her was uncanny and immediate in American Gods. It's entirely possible that Doyle was Doyle before he went into Sweeney's hoard and when he came out he was something - or someone - different. Though Laura finally dumping Mad Sweeney's ashes away in the river indicates that she's finally let him go for good, it's hard to imagine a god-king could ever truly die, or that the writers would introduce a storyline as significant as a transformative romance between them only for it to ultimately be completely pointless.
Liam Doyle being a reincarnation of Mad Sweeney would be a smart way to address a few problems. Pablo Schreiber left the show after season 2 and he's been busy since, particularly filming the lead role of Master Chief in Paramount+'s upcoming live-action adaptation of Halo. A series like that is a time-consuming commitment. Having Iwan Rheon's Doyle be Mad Sweeney reincarnated kills two birds with one stone: It returns the fan-favorite Mad Sweeney to American Gods season 3 and enables them to explore a romance between him and Laura Moon while not having to worry about working around Schreiber's schedule. It would certainly be a welcome twist.