The Big Bang Theory: Sheldon and Amy's romantic milestones

At the behest of Raj (Kunal Nayyar) and Howard's (Simon Helberg) "blackmail," Sheldon (Jim Parsons) begrudgingly agrees to meet Dr. Amy Farrah Fowler (Mayim Bialik). When Amy warns Sheldon there won't be any physical contact, he offers to buy her a drink ("Tepid water, please.") and the rest is history.

It wouldn't be Shamy if it was run-of-the-mill, and, true to form, neither was their first date. Chauffeured and supervised by Penny (Kaley Cuoco), the episode marks Sheldon's first date with not just Amy, but anyone. Following that success, Sheldon makes the executive decision to move things to the next step: "to gift humanity with our progeny."

Shamy begins and ends, and Sheldon gets a lot of cats to cope before Mama Cooper (Laurie Metcalf) swoops in and gets the two geniuses back together — platonically — to, at least, get rid of the smell of six cats.

In an attempt to gauge how Sheldon makes her feel — a.k.a. if she gets turned on by him — Amy holds his hand, but, alas, nothing.

While they technically shared their first kiss way back in season 3 — during the same awkward episode in which they met — Sheldon and Amy didn't share a real, romantic, swoonworthy kiss until their train-bound smooch, just in time for Valentine's Day.

It took another two seasons from their first non-cringeworthy kiss for Shamy to finally — as Sheldon would say — engage in coitus.

It's yet another season before Sheldon takes his relationship with Amy to the next level. Despite her attempt to thwart the couple's relationship, Dr. Ramona Nowitzki (Riki Lindhome) kissing Sheldon only pushes him to finally get down on one knee and pop the question...to Amy, of course. 

Leave it up to the two lovebird scientists to delay their wedding for a chance to nose out an undiscovered physics phenomenon. However, they eventually proceed down the aisle — with Sheldon's idol Luke Skywalker (well, Mark Hamill) officiating their marriage and Amy looking like a "pile of swans" in her white dress. 

First comes love, then comes marriage, then comes a...Nobel Prize. Sheldon and Amy spend their first stage of marriage earning recognition from the world's most prestigious award for their discovery of super asymmetry. Now, that's what we call a power couple!