A look at tonight's sci-fi TV:
Fringe, "What Lies Below" – Fringe returns with a sure-to-be gross episode that kicks off with a man's blood literally bursting out of his arteries and veins. Walter breaks the case with his usual mad science skills, but it's a race against the clock once Peter and Olivia are trapped in a CDC quarantine. (9 p.m. ET on Fox)
The Vampire Diaries, "Bloodlines" – Damon travels to Georgia to find a former flame who can help him open the tomb. Things get complicated when he's forced to confront an old rival on the trip. Firefly's Gina Torres guest stars. (8 p.m. ET on The CW)
Supernatural, "Sam, Interrupted" – This sounds like another fun one: Sam and Dean go undercover at a mental hospital, but they soon discover that it might be the perfect place for them to resolve some of their issues. (9 p.m. ET on The CW)
Archer, "Diversity Hire" – ISIS gets a new field agent, but is he hiding a secret under his perfect façade? (10 p.m. ET on FX)
Head after the jump for clips and more TV picks.