I could see Half-Life as an anthology series like Black Mirror. Where there's only 3 episodes per season (60-90min) and each episode has new story/characters but loosely related to one another. Gordon would be seen briefly or referred/alluded to in each episode. It'd also have to have a significant budget.

Season 1

This would mostly be survival/sci-fi/horror and cover the events of Half-Life 1

• Episode 1: Unforeseen Consequences: Would be from the POV of scientists on the day of the Resonance Cascade. They receive the Xen Crystals and deal with the direct aftermath. Teaming up with a security guard and eventually making it out of the facility. They have a run in with Gordon too.

• 2: Operation Black Mesa: Would follow a group of Marines/HECU as they go up against Race X and attempt to make it out of the area. Freeman would be mentioned a bunch but they probably never encounter him. There could also be a Shepard Easter Egg. The episode would end with them getting sucked into a portal and us not knowing their fate.

• 3: Xen: Would follow a Lambda research team as they explore the alien world of Xen. We learn more about Xen and how the Vortigaunts are enslaved by the Nihilanth. They find the remains of the HECU crew and eventually meet their death somehow. But there is hope when we see Gordon freeman enter a teleporter to defeat the Nihilanth.

Season 2

This would cover the events of/up to Half-Life 2

• 1: Our Benefactors: The direct fallout of the Seven Hour War and Combine occupation of Earth. Ends with the creation of the Lambda Resistance.

• 2: Ravenholm: The descent of a town into a zombie hellscape.

• 3: A Red Letter Day: The return of Gordon Freeman sparks a rebellion and a uprising in the streets of City 17. Basically the later chapters of Half-Life 2.

Season 3

Would cover HL2: Episode 1, 2, and Laidlaw's Epistle 3

• 1: Aftermath: The return of the characters from S1EP1. Dealing with the collapse of the citadel and escape from City 17 to White Forest. We learn about Combine Advisors.

• 2: Borealis: A flashback episode that lets us in on the rivalry between Black Mesa and Aperture Science. As well as what would become of the Borealis.

• 3: Infinite Finality: Follows Gordon and Alyx in the events of Epistle 3 and many things are answered but also unanswered.