WHAT CHARLES YU DOES VERY WELL — it is a long list, but this may be its most notable entry — is to create strange and disturbingly normal alternate realities. In his first novel, How To Live Safely In a Science Fictional Universe, Yu conceived of Minor Universe 31, a universe filled with people widely, albeit unhappily, using time machines. He took sci-fi theories and ran them through a sort of literary normalizer, applying ample wit, pop-culture references, psychological insight, metaphorical flair, and a vital sweetness (his young, isolated protagonist, in search of his father, even has a stray dog for a pet). Overflowing with quasi-scientific jargon, the novel was exciting and funny and, at times, downright spooky, much like the quantum theories that Yu invoked. But most of all, for a story about a time travel mechanic, it was unfailingly realistic.

In his new collection of stories, Sorry Please Thank You, Yu no longer constrains himself to the pre-requisites of realism — or, to be more accurate, the appearance of realism. Freed from this yoke, he takes off in every narrative direction with the glee of a school-kid released for summer vacation. Set in a video game world reminiscent of the 1980s arcade hit, Gauntlet, “Hero Absorbs Major Damage” is a geeky, tongue-in-cheek adventure tale about a hack n’ slash video game warrior suffering a crisis of confidence. “Yeoman” follows the imperiled final week of a crewmember on a Star Trek-like voyage as he grapples with a homicidally bored captain. “The Book of Categories” debates the existence of a mysterious book — a formally intriguing, hypnotic story that reads as if a Zen koan had been rewritten for a computer operating system. And then there is “Designer Emotion,” a cheerfully cynical monologue delivered at the board meeting of a pharmaceutical company that formulates emotions. Besides Yu’s exuberant inventiveness, the stories’ only easily observable commonalities are timorous first-person narrators who usually mean well or second-person narrators who instruct, challenge, and occasionally discomfit, and a sly sense of humor that carbonates the lighter stories and lightens the darker stories.

Of course, any focus on innovation will result in a few missteps, and that such a sustained demonstration of originality and experimentation can inspire a complaint illustrates just how thankless it is to be a fiction writer. Nevertheless, there are some entrants in the collection that spin out of control. Halfway through an odd, gauzy story about an enigmatic protagonist named Charles Yu, “Inventory” starts to feel overly long, its scrupulous vagueness slipping toward blandness; and “Open,” a dark story about a trans-dimensional apartment swap that imperils a romantic relationship, offers a meta-fictional ending that sounds correct, but there is something hasty and unconvincing about it, as if Yu simply pressed the Ambiguous Lyrical Conclusion button on his keyboard. But these are, admittedly, quibbles, and if they are the cost for the conception of a magnificent story like “Standard Loneliness Package,” well worth it.

Set in an epoch when technology allows emotions to be bundled into packets of information and electronically transmitted, “Standard Loneliness Package” details the life of a young worker at a company that outsources grief and pain. Despite t...