Spoiler alert! The following contains plot details through Season 3, Episode 4 of “Bridgerton.”

Netflix’s “Bridgerton” has returned, and it seems almost desperate for some action this time around.

It’s not all prim dresses and shy glances in Regency England in the streamer’s historical romance, which is now streaming the first half of its eight-episode third season (the second half is due June 13). The series is famous for its steamy bedroom scenes from Season 1, which turned honeymoon high jinks into a mating montage as Daphne (Phoebe Dynevor) and Simon (Regé-Jean Page) consummated their marriage.

Season 2 was criticized for keeping things rathermore chaste, so, seemingly in response, Season 3 ups the amorous ante, cramming in coitus wherever it can. Sometimes it’s a welcome dose of fireworks; other times it’s futile and cold.

Sex scenes have been a part of TV for decades, but they’ve never been more prevalent than in the age of streaming, which like premium cable is uninhibited by pesky FCC regulations holding back mature content.

But the return of “Bridgerton” made us wonder: What makes a good TV sex scene? What makes one series full of passion and and another painfully robotic? How much skin is too much? How much is too little? So for any TV producers looking to add sizzle to their stories, we offer a guide to seemly but not boring sex on TV. Clutch your pearls and read on.

What makes a good sex scene? Emotional investment

When it comes to hanky panky, it helps if you care.

Maybe I sound like your mother giving the sex talk, but all TV is a relationship between characters and the audience. Sometimes you hate the protagonists (or even love to hate them). But in romance? We need to be in love just as much as the fictional people are.

Daphne and Simon’s love was visceral. The stakes were high: In one scene, Daphne’s brother Anthony (Jonathan Bailey) engages Simon in a duel over Simon’s refusal to propose to Daphne after a hot make out session. The chemistry between Page and Dynevor practically boiled over. When the clothes came off, it was as exciting as a big battle scene in an action film. It was the perfect climax to their story, pun intended.

In Season 3 it takes four long episodes, but “Bridgerton” recreates some of that heat with Penelope and Colin by keeping the camera trained on Penelope, a character it is hard not to love. When the pair finally admits their mutual attraction in a speeding horse-drawn carriage and gets physical, the focus is on Pen and her experience. Colin may be a boring beau, but at least he makes her happy.

Random nudity never works

There were several infamous sex scenes over eight seasons of “Game of Thrones.” Not the rape scenes (controversial in their own right) or even the “sexposition scenes” (in which backstory is told during sexual encounters, a favorite “Thrones” tactic), but random intimacy with no context that feels not at all intimate. Mostly set at brothels, you’ll see extras engaging in sexual acts, women walking around topless for no reason, lewd dialogue and other sexual scenarios. They didn’t involve the main characters much, nor did they contribute to the plot.

Sex and nudity as background dressing is tired and dull, awkward and not “sexy” in any sense of the word. “Bridgerton” employs this to its disadvantage in the new season, putting wooden Colin (Luke Newton) in two separate threesomes with prostitutes, a jarring shift in tone from the rest of the series.

Play coy, until you don’t have to

But we are talking about intimacy here, so there are no brownie points for the most clothes left on. Nudity has a time and place, and some series understand how to tastefully get raunchy without losing the literal plot.

Starz, long the reigning king (or queen) of steamy premium-cable intimacy, has yet another hot and bothered drama this season, “Mary & George” (finale airs Friday, 9 EDT/PDT). The series, set in the 17th century, stars Julianne Moore and young up-and-comer Nicholas Galitzine. There is very little left to the imagination in the lusty affair between Galitzine’s George Villiers and Tony Curran’s King James I.

When George and James finally consummate their affair, it is not with the pure intentions of Daphne and Simon; this is politics. George’s mother Mary (Moore) has urged her son to seduce the King to gain wealth and power in the British court. But the actors and writers get the pacing, aesthetics and movements just right to bring all of the intensity without any of the romance.

Sex on TV doesn’t have to be slow or sweet, coy or romantic to be worthwhile. It also doesn’t have to verge into pornography. Finding that middle ground that serves your characters, story and audience without becoming tasteless or pointless is difficult. Many a great TV show has fumbled in the bedroom: Showtime’s “Shameless,” HBO’s recently-canceled “The Idol” and CW’s “Gossip Girl,” to name a few.

But then there are the scenes so memorable they make the show better. Fox and Netflix’s “Lucifer” answered the will-they-or-won’t-they of its two leads in a fiery Season 5 episode. Starz’s “Outlander” was known for its sensitive and female-forward sex. Hulu’s “Normal People” had a legion of fans drooling over Paul Mescal’s Connell and his long romance with Marianne (Daisy Edgar-Jones).

It is possible to get hot without getting hackneyed. Producers should take note for “Bridgerton” Season 4.